Athena Widget Set - C Language Interface

X Consortium Standard

Chris Peterson

   X Version 11, Release 6.4

   libXaw 1.0.7

   Copyright (c) 1985 X Consortium

   Copyright (c) 1986 X Consortium

   Copyright (c) 1987 X Consortium

   Copyright (c) 1988 X Consortium

   Copyright (c) 1989 X Consortium

   Copyright (c) 1991 X Consortium

   Copyright (c) 1994 X Consortium

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   Table of Contents

   1. Athena Widgets and The Intrinsics

        Introduction to the X Toolkit
        Terminology
        Underlying Model
        Conventions Used in this Manual
        Format of the Widget Reference Chapters
        Input Focus

   2. Using Widgets

        Using Widgets

              Setting the Locale
              Initializing the Toolkit
              Creating a Widget
              Common Resources
              Resource Conversions
              Realizing a Widget
              Processing Events
              Standard Widget Manipulation Functions
              Using the Client Callback Interface
              Programming Considerations
              Example Programs

   3. Simple Widgets

        Command Widget

              Resources
              Command Actions

        Grip Widget

              Resources
              Grip Actions

        Label Widget

              Resources

        List Widget

              Resources
              List Actions
              List Callbacks
              Changing the List
              Highlighting an Item
              Unhighlighting an Item
              Retrieving the Currently Selected Item
              Restrictions

        Panner Widget

              Resources
              Panner Actions
              Panner Callbacks

        Repeater Widget

              Resources
              Repeater Actions

        Scrollbar Widget

              Resources
              Scrollbar Actions
              Scrollbar Callbacks
              Convenience Routines
              Setting Float Resources

        Simple Widget

              Resources

        StripChart Widget

              Resources
              Getting the StripChart Value

        Toggle Widget

              Resources
              Toggle Actions
              Toggle Actions_b
              Radio Groups
              Convenience Routines

   4. Menus

        Using the Menus
        Sme Object

              Resources
              Subclassing the Sme Object

        SmeBSB Object

              Resources

        SmeLine Object

              Resources

   5. Text Widgets

        Text Widget for Users

              Default Key Bindings
              Search and Replace
              File Insertion
              Text Selections for Users

        Text Widget Actions

              Cursor Movement Actions\fP
              Delete Actions
              Selection Actions
              The New Line Actions
              Kill and Actions
              Miscellaneous Actions
              Text Selections for Application Programmers

        Default Translation Bindings
        Text Functions

              Selecting Text
              Unhighlighting Text
              Getting Current Text Selection
              Replacing Text
              Searching for Text
              Redisplaying Text
              Resources Convenience Routines

        Customizing the Text Widget
        Text Widget

              Resources

        TextSink Object

              Resources
              Subclassing the TextSink

        TextSrc Object

              Resources
              Subclassing the TextSrc

        Ascii Sink Object and Multi Sink Object

              Resources

        Ascii Source Object and Multi Source Object

              Resources
              Convenience Routines

        Ascii Text Widget

              Resources

   6. Composite and Constraint Widgets

        Box Widget

              Resources
              Layout Semantics

        Dialog Widget

              Resources
              Constraint Resources
              Layout Semantics
              Automatically Created Children.
              Convenience Routines

        Form Widget

              Resources
              Constraint Resources
              Layout Semantics
              Convenience Routines

        Paned Widget

              Using the Paned Widget
              Resources
              Constraint Resources
              Layout Semantics
              Grip Translations
              Convenience Routines

        Porthole Widget

              Resources
              Layout Semantics
              Porthole Callbacks

        Tree Widget

              Resources
              Constraint Resources
              Layout Semantics
              Convenience Routines

        Viewport Widget

              Resources
              Layout Semantics

   7. Creating New Widgets (Subclassing)

        Public Header File
        Private Header File
        Widget Source File

   8. Acknowledgments

Chapter 1. Athena Widgets and The Intrinsics

   Table of Contents

   Introduction to the X Toolkit
   Terminology
   Underlying Model
   Conventions Used in this Manual
   Format of the Widget Reference Chapters
   Input Focus

   The X Toolkit is made up of two distinct pieces, the Xt
   Intrinsics and a widget set. The Athena widget set is a sample
   implementation of a widget set built upon the Intrinsics. In
   the X Toolkit, a widget is the combination of an X window or
   subwindow and its associated input and output semantics.

   Because the Intrinsics provide the same basic functionality to
   all widget sets it may be possible to use widgets from the
   Athena widget set with other widget sets based upon the
   Intrinsics. Since widget sets may also implement private
   protocols, all functionality may not be available when mixing
   and matching widget sets. For information about the Intrinsics,
   see the X Toolkit Intrinsics - C Language Interface.

   The Athena widget set is a library package layered on top of
   the Intrinsics and Xlib that provides a set of user interface
   tools sufficient to build a wide variety of applications. This
   layer extends the basic abstractions provided by X and provides
   the next layer of functionality primarily by supplying a
   cohesive set of sample widgets. Although the Intrinsics are a
   Consortium standard, there is no standard widget set.

   To the extent possible, the Intrinsics are "policy-free". The
   application environment and widget set, not the Intrinsics,
   define, implement, and enforce:
     * Policy
     * Consistency
     * Style

   Each individual widget implementation defines its own policy.
   The X Toolkit design allows for, but does not necessarily
   encourage, the free mixing of radically differing widget
   implementations.

Introduction to the X Toolkit

   The X Toolkit provides tools that simplify the design of
   application user interfaces in the X Window System programming
   environment. It assists application programmers by providing a
   set of common underlying user-interface functions. It also lets
   widget programmers modify existing widgets, by subclassing, or
   add new widgets. By using the X Toolkit in their applications,
   programmers can present a similar user interface across
   applications to all workstation users.

   The X Toolkit consists of:
     * A set of Intrinsics functions for building widgets
     * An architectural model for constructing widgets
     * A widget set for application programming

   While the majority of the Intrinsics functions are intended for
   the widget programmer, a subset of the Intrinsics functions are
   to be used by application programmers (see X Toolkit Intrinsics
   - C Language Interface). The architectural model lets the
   widget programmer design new widgets by using the Intrinsics
   and by combining other widgets. The application interface
   layers built on top of the X Toolkit include a coordinated set
   of widgets and composition policies. Some of these widgets and
   policies are specific to a single application domain, and
   others are common to a variety of applications.

   The remainder of this chapter discusses the X Toolkit and
   Athena widget set:
     * Terminology
     * Model
     * Conventions used in this manual
     * Format of the Widget Reference Chapters

Terminology

   In addition to the terms already defined for X programming (see
   Xlib - C Language Interface), the following terms are specific
   to the Intrinsics and Athena widget set and used throughout
   this document.

   Application programmer
     * A programmer who uses the X Toolkit to produce an
       application user interface.

   Child
     * A widget that is contained within another "parent" widget.

   Class
     * The general group to which a specific object belongs.

   Client
     * A function that uses a widget in an application or for
       composing other widgets.

   FullName
     * The name of a widget instance appended to the full name of
       its parent.

   Instance
     * A specific widget object as opposed to a general widget
       class.

   Method
     * A function or procedure implemented by a widget class.

   Name
     * The name that is specific to an instance of a widget for a
       given client. This name is specified at creation time and
       cannot be modified.

   Object
     * A data abstraction consisting of private data and private
       and public functions that operate on the private data.
       Users of the abstraction can interact with the object only
       through calls to the object's public functions. In the X
       Toolkit, some of the object's public functions are called
       directly by the application, while others are called
       indirectly when the application calls the common Intrinsics
       functions. In general, if a function is common to all
       widgets, an application uses a single Intrinsics function
       to invoke the function for all types of widgets. If a
       function is unique to a single widget type, the widget
       exports the function.

   Parent
     * A widget that contains at least one other ("child") widget.
       A parent widget is also known as a composite widget.

   Resource
     * A named piece of data in a widget that can be set by a
       client, by an application, or by user defaults.

   Superclass
     * A larger class of which a specific class is a member. All
       members of a class are also members of the superclass.

   User
     * A person interacting with a workstation.

   Widget
     * An object providing a user-interface abstraction (for
       example, a Scrollbar widget).

   Widget class
     * The general group to which a specific widget belongs,
       otherwise known as the type of the widget.

   Widget programmer
     * A programmer who adds new widgets to the X Toolkit.

Underlying Model

   The underlying architectural model is based on the following
   premises:
     *
     * Every user-interface widget is associated with an X window.
       The X window ID for a widget is readily available from the
       widget. Standard Xlib calls can be used by widgets for many
       of their input and output operations.
     *
     * The data for every widget is private to the widget and its
       subclasses. That is, the data is neither directly
       accessible nor visible outside of the module implementing
       the widget. All program interaction with the widget is
       performed by a set of operations (methods) that are defined
       for the widget.
     *
     * Widget semantics are clearly separated from widget layout
       geometry. Widgets are concerned with implementing specific
       user-interface semantics. They have little control over
       issues such as their size or placement relative to other
       widget peers. Mechanisms are provided for associating
       geometric managers with widgets and for widgets to make
       suggestions about their own geometry.

Conventions Used in this Manual

     * All resources available to the widgets are listed with each
       widget. Many of these are available to more than one widget
       class due to the object oriented nature of the Intrinsics.
       The new resources for each widget are listed in bold text,
       and the inherited resources are listed in plain text.
     * Global symbols are printed in bold and can be function
       names, symbols defined in include files, or structure
       names. Arguments are printed in italics.
     * Each function is introduced by a general discussion that
       distinguishes it from other functions. The function
       declaration itself follows, and each argument is
       specifically explained. General discussion of the function,
       if any is required, follows the arguments. Where
       applicable, the last paragraph of the explanation lists the
       return values of the function.
     * To eliminate any ambiguity between those arguments that you
       pass and those that a function returns to you, the
       explanations for all arguments that you pass start with the
       word specifies or, in the case of multiple arguments, the
       word specify. The explanations for all arguments that are
       returned to you start with the word returns or, in the case
       of multiple arguments, the word return. The explanations
       for all arguments that you can pass and are returned start
       with the words specifies and returns.
     * Any pointer to a structure that is used to return a value
       is designated as such by the _return suffix as part of its
       name. All other pointers passed to these functions are used
       for reading only. A few arguments use pointers to
       structures that are used for both input and output and are
       indicated by using the _in_out suffix.

Format of the Widget Reference Chapters

   The majority of this document is a reference guide for the
   Athena widget set. Chapters three through six give the
   programmer all information necessary to use the widgets. The
   layout of the chapters follows a specific pattern to allow the
   programmer to easily find the desired information.

   The first few pages of every chapter give an overview of the
   widgets in that section. Widgets are grouped into chapters by
   functionality.

   "Chapter
          Simple Widgets

   "Chapter
          Menus

   "Chapter
          Text Widgets

   "Chapter
          Composite and Constraint Widget

   Following the introduction will be a description of each widget
   in that chapter. When no functional grouping is obvious the
   widgets are listed in alphabetical order, such as in chapters
   three and six.

   The first section of each widget's description is a table that
   contains general information about this widget class. Here is
   the table for the Box widget, and an explanation of all the
   entries.



Application Header file <X11/Xaw/Box.h>
Class Header file       <X11/Xaw/BoxP.h>
Class           boxWidgetClass
Class Name      Box
Superclass      Composite


   Application Header File
          This file must be included when an application uses this
          widget. It usually contains the class definition, and
          some resource macros. This is often called the
          ``public'' header file.

   Class Header File
          This file will only be used by widget programmers. It
          will need to be included by any widget that subclasses
          this widget. This is often called the ``private'' header
          file.

   Class
          This is the widget class of this widget. This global
          symbol is passed to XtCreateWidget so that the
          Intrinsics will know which type of widget to create.

   Class Name
          This is the resource name of this class. This name can
          be used in a resource file to match any widget of this
          class.

   Superclass
          This is the superclass that this widget class is
          descended from. If you understand how the superclass
          works it will allow you to more quickly understand what
          this widget does, since much of its functionality may be
          inherited from its superclass.

   After this table follows a general description of the default
   behavior of this widget, as seen by the user. In many cases
   this functionality may be overridden by the application
   programmer, or by the user.

   The next section is a table showing the name, class, type and
   default value of each resource that is available to this
   widget. There is also a column containing notes describing
   special restrictions placed upon individual resources.

   A
          This resource may be automatically adjusted when another
          resource is changed.

   C
          This resource is only settable at widget creation time,
          and may not be modified with XtSetValues.

   D
          Do not modify this resource. While setting this resource
          will work, it can cause unexpected behavior. When this
          symbol appears there is another, preferred, interface
          provided by the X Toolkit.

   R
          This resource is READ-ONLY, and may not be modified.

   After the resource table is a detailed description of every
   resource available to that widget. Many of these are redundant,
   but printing them with each widget saves page flipping. The
   names of the resources that are inherited are printed in plain
   text, while the names of the resources that are new to this
   class are printed in bold. If you have already read the
   description of the superclass you need only pay attention to
   the resources printed in bold.

   For each composite widget there is a section on layout
   semantics that follows the resource description. This section
   will describe the effect of constraint resources on the layout
   of the children, as well as a general description of where it
   prefers to place its children.

   Descriptions of default translations and action routines come
   next, for widgets to which they apply. The last item in each
   widget's documentation is the description of all convenience
   routines provided by the widget.

Input Focus

   The Intrinsics define a resource on all Shell widgets that
   interact with the window manager called input. This resource
   requests the assistance of window manager in acquiring the
   input focus. The resource defaults to False in the Intrinsics,
   but is redefined to default to True when an application is
   using the Athena widget set. An application programmer may
   override this default and set the resource back to False if the
   application does not need the window manager to give it the
   input focus. See the X Toolkit Intrinsics - C Language
   Interface for details on the input resource.

Chapter 2. Using Widgets

   Table of Contents

   Using Widgets

        Setting the Locale
        Initializing the Toolkit
        Creating a Widget
        Common Resources
        Resource Conversions
        Realizing a Widget
        Processing Events
        Standard Widget Manipulation Functions
        Using the Client Callback Interface
        Programming Considerations
        Example Programs

Using Widgets

   Widgets serve as the primary tools for building a user
   interface or application environment. The Athena widget set
   consists of primitive widgets that contain no children (for
   example, a command button) and composite widgets which may
   contain one or more widget children (for example, a Box
   widget).

   The remaining chapters explain the widgets that are provided by
   the Athena widget set. These user-interface components serve as
   an interface for application programmers who do not want to
   implement their own widgets. In addition, they serve as a
   starting point for those widget programmers who, using the
   Intrinsics mechanisms, want to implement alternative
   application programming interfaces.

   This chapter is a brief introduction to widget programming. The
   examples provided use the Athena widgets, though most of the
   concepts will apply to all widget sets. Although there are
   several programming interfaces to the X Toolkit, only one is
   described here. A full description of the programming interface
   is provided in the document X Toolkit Intrinsics - C Language
   Interface.

Setting the Locale

   If it is desirable that the application take advantage of
   internationalization (i18n), you must establish locale with
   XtSetLanguageProc before XtDisplayInitialize or XtAppInitialize
   is called. For full details, please refer to the document X
   Toolkit Intrinsics - C Language Interface, section 2.2.
   However, the following simplest-case call is sufficient in many
   or most applications.



        XtSetLanguageProc(NULL, NULL, NULL);

   Most notably, this will affect the Standard C locale, determine
   which resource files will be loaded, and what fonts will be
   required of FontSet specifications. In many cases, the addition
   of this line is the only source change required to
   internationalize Xaw programs, and will not disturb the
   function of programs in the default "C" locale.

Initializing the Toolkit

   You must call a toolkit initialization function before invoking
   any other toolkit routines (besides locale setting, above).
   XtAppInitialize opens the X server connection, parses the
   command line, and creates an initial widget that will serve as
   the root of a tree of widgets created by this application.
   Widget XtAppInitialize( app_context_return,
                           application_class,
                           options,
                           num_options,
                           *argc_in_out,
                           *argv_in_out,
                           *fallback_resources,
                           args,
                           num_args);
   XtAppContext app_context_return;
   String application_class;
   XrmOptionDescRec options;
   Cardinal num_options;
   int *argc_in_out;
   String *argv_in_out;
   String *fallback_resources;
   ArgList args;
   Cardinal num_args;

   app_con_return
          Returns the application context of this application, if
          non-NULL.

   application_class
          Specifies the class name of this application, which is
          usually the generic name for all instances of this
          application. A useful convention is to form the class
          name by capitalizing the first letter of the application
          name. For example, the application named ``xman'' has a
          class name of ``Xman''.

   options
          Specifies how to parse the command line for any
          application-specific resources. The options argument is
          passed as a parameter to XrmParseCommand . For further
          information, see Xlib - C Language Interface.

   num_options
          Specifies the number of entries in the options list.

   argc_in_out
          Specifies a pointer to the number of command line
          parameters.

   argv_in_out
          Specifies the command line parameters.

   fallback_resources
          Specifies resource values to be used if the site-wide
          application class defaults file cannot be opened, or
          NULL.

   args
          Specifies the argument list to use when creating the
          Application shell.

   num_args
          Specifies the number of arguments in args.

   This function will remove the command line arguments that the
   toolkit reads from argc_in_out, and argv_in_out. It will then
   attempt to open the display. If the display cannot be opened,
   an error message is issued and XtAppInitialize terminates the
   application. Once the display is opened, all resources are read
   from the locations specified by the Intrinsics. This function
   returns an ApplicationShell widget to be used as the root of
   the application's widget tree.

Creating a Widget

   Creating a widget is a three-step process. First, the widget
   instance is allocated, and various instance-specific attributes
   are set by using XtCreateWidget. Second, the widget's parent is
   informed of the new child by using XtManageChild. Finally, X
   windows are created for the parent and all its children by
   using XtRealizeWidget and specifying the top-most widget. The
   first two steps can be combined by using XtCreateManagedWidget.
   In addition, XtRealizeWidget is automatically called when the
   child becomes managed if the parent is already realized.

   To allocate, initialize, and manage a widget, use
   XtCreateManagedWidget .
   Widget XtCreateManagedWidget( name,
                                 widget_class,
                                 parent,
                                 args,
                                 num_args);
   String name;
   WidgetClass widget_class;
   Widget parent;
   ArgList args;
   Cardinal num_args;

   name
          Specifies the instance name for the created widget that
          is used for retrieving widget resources.

   widget_class
          Specifies the widget class pointer for the created
          widget.

   parent
          Specifies the parent widget ID.

   args
          Specifies the argument list. The argument list is a
          variable-length list composed of name and value pairs
          that contain information pertaining to the specific
          widget instance being created. For further information,
          see Section 2.7.2.

   num_args
          Specifies the number of arguments in the argument list.
          If the num_args is zero, the argument list is never
          referenced.

   When a widget instance is successfully created, the widget
   identifier is returned to the application. If an error is
   encountered, the XtError routine is invoked to inform the user
   of the error.

   For further information, see X Toolkit Intrinsics - C Language
   Interface.

Common Resources

   Although a widget can have unique arguments that it
   understands, all widgets have common arguments that provide
   some regularity of operation. The common arguments allow
   arbitrary widgets to be managed by higher-level components
   without regard for the individual widget type. Widgets will
   ignore any argument that they do not understand.

   The following resources are retrieved from the argument list or
   from the resource database by all of the Athena widgets:
      Name              Class             Type          Default Value
  accelerators      Accelerators    AcceleratorTable        NULL
ancestorSensitive AncestorSensitive     Boolean             True
   background        Background          Pixel       XtDefaultBackground
backgroundPixmap       Pixmap            Pixmap      XtUnspecifiedPixmap
   borderColor       BorderColor         Pixel       XtDefaultForeground
  borderPixmap         Pixmap            Pixmap      XtUnspecifiedPixmap
   borderWidth       BorderWidth       Dimension              1
    colormap          Colormap          Colormap      Parent's Colormap
      depth             Depth             int          Parent's Depth
 destroyCallback      Callback       XtCallbackList         NULL
     height            Height          Dimension      widget dependent
mappedWhenManaged MappedWhenManaged     Boolean             True
     screen            Screen            Screen        Parent's Screen
    sensitive         Sensitive         Boolean             True
  translations      Translations    TranslationTable  widget dependent
      width             Width          Dimension      widget dependent
        x             Position          Position              0
        y             Position          Position              0

   The following additional resources are retrieved from the
   argument list or from the resource database by many of the
   Athena widgets:
         Name           Class         Type         Default Value
       callback       Callback   XtCallbackList        NULL
        cursor         Cursor        Cursor      widget dependent
      foreground     Foreground      Pixel      XtDefaultForeground
   insensitiveBorder Insensitive     Pixmap         GreyPixmap

Resource Conversions

   Most resources in the Athena widget set have a converter
   registered that will translate the string in a resource file to
   the correct internal representation. While some are obvious
   (string to integer, for example), others need specific mention
   of the allowable values. Three general converters are described
   here:
     * Cursor
     * Pixel
     * Bitmap

   Many widgets have defined special converters that apply only to
   that widget. When these occur, the documentation section for
   that widget will describe the converter.

Cursor Conversion

   The value for the cursorName resource is specified in the
   resource database as a string, and is of the following forms:
     * A standard X cursor name from < X11/cursorfont.h >. The
       names in cursorfont.h each describe a specific cursor. The
       resource names for these cursors are exactly like the names
       in this file except the XC_ is not used. The cursor
       definition XC_gumby has a resource name of gumby.
     * Glyphs, as in FONT font-name glyph-index [[ font-name ]
       glyph-index ]. The first font and glyph specify the cursor
       source pixmap. The second font and glyph specify the cursor
       mask pixmap. The mask font defaults to the source font, and
       the mask glyph index defaults to the source glyph index.
     * A relative or absolute file name. If a relative or absolute
       file name is specified, that file is used to create the
       source pixmap. Then the string "Mask" is appended to locate
       the cursor mask pixmap. If the "Mask" file does not exist,
       the suffix "msk" is tried. If "msk" fails, no cursor mask
       will be used. If the filename does not start with '/' or
       './' the the bitmap file path is used (see section 2.4.3).

Pixel Conversion

   The string-to-pixel converter takes any name that is acceptable
   to XParseColor (see Xlib - C Language Interface). In addition
   this routine understands the special toolkit symbols
   `XtDefaultForeground' and `XtDefaultBackground', described in X
   Toolkit Intrinsics - C Language Interface. In short the
   acceptable pixel names are:
     * Any color name for the rgb.txt file (typically in the
       directory /usr/lib/X11 on POSIX systems).
     * A numeric specification of the form #<red><green><blue>
       where these numeric values are hexadecimal digits (both
       upper and lower case).
     * The special strings `XtDefaultForeground' and
       `XtDefaultBackground'

Bitmap Conversion

   The string-to-bitmap converter attempts to locate a file
   containing bitmap data whose name is specified by the input
   string. If the file name is relative (i.e. does not begin with
   / or ./), the directories to be searched are specified in the
   bitmapFilePath resource--class BitmapFilePath. This resource
   specifies a colon (:) separated list of directories that will
   be searched for the named bitmap or cursor glyph (see section
   2.4.1). The bitmapFilePath resource is global to the
   application, and may not be specified differently for each
   widget that wishes to convert a cursor to bitmap. In addition
   to the directories specified in the bitmapFilePath resource a
   default directory is searched. When using POSIX the default
   directory is /usr/include/X11/bitmaps .

Realizing a Widget

   The XtRealizeWidget function performs two tasks:
     * Calculates the geometry constraints of all managed
       descendants of this widget. The actual calculation is put
       off until realize time for performance reasons.
     * Creates an X window for the widget and, if it is a
       composite widget, realizes each of its managed children.

       void XtRealizeWidget( w);
       Widget w;

     * Specifies the widget.

   For further information about this function, see the X Toolkit
   Intrinsics - C Language Interface.

Processing Events

   Now that the application has created, managed and realized its
   widgets, it is ready to process the events that will be
   delivered by the X Server to this client. A function call that
   will process the events is XtAppMainLoop.
   void XtAppMainLoop( app_context);
   XtAppContext app_context;

   app_context
          Specifies the application context of this application.
          The value is normally returned by XtAppInitialize.

   This function never returns: it is an infinite loop that
   processes the X events. User input can be handled through
   callback procedures and application defined action routines.
   More details are provided in X Toolkit Intrinsics - C Language
   Interface.

Standard Widget Manipulation Functions

   After a widget has been created, a client can interact with
   that widget by calling one of the standard widget manipulation
   routines provided by the Intrinsics, or a widget class-specific
   manipulation routine.

   The Intrinsics provide generic routines to give the application
   programmer access to a set of standard widget functions. The
   common widget routines let an application or composite widget
   perform the following operations on widgets without requiring
   explicit knowledge of the widget type.
     * Control the mapping of widget windows
     * Destroy a widget instance
     * Obtain an argument value
     * Set an argument value

Mapping Widgets

   By default, widget windows are mapped (made viewable)
   automatically by XtRealizeWidget. This behavior can be disabled
   by using XtSetMappedWhenManaged, making the client responsible
   for calling XtMapWidget to make the widget viewable.
   void XtSetMappedWhenManaged( w,
                                map_when_managed);
   Widget w;
   Boolean map_when_managed;

   w
          Specifies the widget.

   map_when_managed
          Specifies the new value. If map_when_managed is True,
          the widget is mapped automatically when it is realized.
          If map_when_managed is False, the client must call
          XtMapWidget or make a second call to
          XtSetMappedWhenManaged to cause the child window to be
          mapped.

   The definition for XtMapWidget is:
   void XtMapWidget( w);
   Widget w;

   w
          Specifies the widget.

   When you are creating several children in sequence for a
   previously realized common parent it is generally more
   efficient to construct a list of children as they are created
   (using XtCreateWidget) and then use XtManageChildren to request
   that their parent managed them all at once. By managing a list
   of children at one time, the parent can avoid wasteful
   duplication of geometry processing and the associated ``screen
   flash''.
   void XtManageChildren( children,
                          num_children);
   WidgetList children;
   Cardinal num_children;

   children
          Specifies a list of children to add.

   num_children
          Specifies the number of children to add.

   If the parent is already visible on the screen, it is
   especially important to batch updates so that the minimum
   amount of visible window reconfiguration is performed.

   For further information about these functions, see the X
   Toolkit Intrinsics - C Language Interface.

Destroying Widgets

   To destroy a widget instance of any type, use XtDestroyWidget
   void XtDestroyWidget( w);
   Widget w;

   w
          Specifies the widget.

   XtDestroyWidget destroys the widget and recursively destroys
   any children that it may have, including the windows created by
   its children. After calling XtDestroyWidget , no further
   references should be made to the widget or any children that
   the destroyed widget may have had.

Retrieving Widget Resource Values

   To retrieve the current value of a resource attribute
   associated with a widget instance, use XtGetValues .
   void XtGetValues( w,
                     args,
                     num_args);
   Widget w;
   ArgList args;
   Cardinal num_args;

   w
          Specifies the widget.

   args
          Specifies a variable-length argument list of name and
          address pairs that contain the resource name and the
          address into which the resource value is stored.

   num_args
          Specifies the number of arguments in the argument list.

   The arguments and values passed in the argument list are
   dependent on the widget. Note that the caller is responsible
   for providing space into which the returned resource value is
   copied; the ArgList contains a pointer to this storage (e.g. x
   and y must be allocated as Position). For further information,
   see the X Toolkit Intrinsics - C Language Interface.

Modifying Widget Resource Values

   To modify the current value of a resource attribute associated
   with a widget instance, use XtSetValues .
   void XtSetValues( w,
                     args,
                     num_args);
   Widget w;
   ArgList args;
   Cardinal num_args;

   w
          Specifies the widget.

   args
          Specifies an array of name and value pairs that contain
          the arguments to be modified and their new values.

   num_args
          Specifies the number of arguments in the argument list.

   The arguments and values that are passed will depend on the
   widget being modified. Some widgets may not allow certain
   resources to be modified after the widget instance has been
   created or realized. No notification is given if any part of a
   XtSetValues request is ignored.

   For further information about these functions, see the X
   Toolkit Intrinsics - C Language Interface. The argument list
   entry for XtGetValues specifies the address to which the caller
   wants the value copied. The argument list entry for XtSetValues
   , however, contains the new value itself, if the size of value
   is less than sizeof(XtArgVal) (architecture dependent, but at
   least sizeof(long)); otherwise, it is a pointer to the value.
   String resources are always passed as pointers, regardless of
   the length of the string.

Using the Client Callback Interface

   Widgets can communicate changes in their state to their clients
   by means of a callback facility. The format for a client's
   callback handler is:
   void CallbackProc( w,
                      client_data,
                      call_data);
   Widget w;
   XtPointer client_data;
   XtPointer call_data;

   w
          Specifies widget for which the callback is registered.

   client_data
          Specifies arbitrary client-supplied data that the widget
          should pass back to the client when the widget executes
          the client's callback procedure. This is a way for the
          client registering the callback to also register
          client-specific data: a pointer to additional
          information about the widget, a reason for invoking the
          callback, and so on. If no additional information is
          necessary, NULL may be passed as this argument. This
          field is also frequently known as the closure.

   call_data
          Specifies any callback-specific data the widget wants to
          pass to the client. For example, when Scrollbar executes
          its jumpProc callback list, it passes the current
          position of the thumb in call_data.

   Callbacks can be registered either by creating an argument
   containing the callback list described below or by using the
   special convenience routines XtAddCallback and XtAddCallbacks.
   When the widget is created, a pointer to a list of callback
   procedure and data pairs can be passed in the argument list to
   XtCreateWidget . The list is of type XtCallbackList :



typedef struct {
        XtCallbackProc callback;
        XtPointer closure;
} XtCallbackRec, *XtCallbackList;

   The callback list must be allocated and initialized before
   calling XtCreateWidget . The end of the list is identified by
   an entry containing NULL in callback and closure. Once the
   widget is created, the client can change or de-allocate this
   list; the widget itself makes no further reference to it. The
   closure field contains the client_data passed to the callback
   when the callback list is executed.

   The second method for registering callbacks is to use
   XtAddCallback after the widget has been created.
   void XtAddCallback( w,
                       callback_name,
                       callback,
                       client_data);
   Widget w;
   String callback_name;
   XtCallbackProc callback;
   XtPointer client_data;

   w
          Specifies the widget to add the callback to.

   callback_name
          Specifies the callback list within the widget to append
          to.

   callback
          Specifies the callback procedure to add.

   client_data
          Specifies the data to be passed to the callback when it
          is invoked.

   XtAddCallback adds the specified callback to the list for the
   named widget.

   All widgets provide a callback list named destroyCallback where
   clients can register procedures that are to be executed when
   the widget is destroyed. The destroy callbacks are executed
   when the widget or an ancestor is destroyed. The call_data
   argument is unused for destroy callbacks.

Programming Considerations

   This section provides some guidelines on how to set up an
   application program that uses the X Toolkit.

Writing Applications

   When writing an application that uses the X Toolkit, you should
   make sure that your application performs the following:
    1. Include < X11/Intrinsic.h > in your application programs.
       This header file automatically includes < X11/Xlib.h >, so
       all Xlib functions also are defined. It may also be
       necessary to include < X11/StringDefs.h > when setting up
       argument lists, as many of the XtNsomething definitions are
       only defined in this file.
    2. Include the widget-specific header files for each widget
       type that you need to use. For example, < X11/Xaw/Label.h >
       and < X11/Xaw/Command.h >.
    3. Call the XtAppInitialize function before invoking any other
       toolkit or Xlib functions. For further information, see
       Section 2.1 and the X Toolkit Intrinsics - C Language
       Interface.
    4. To pass attributes to the widget creation routines that
       will override any site or user customizations, set up
       argument lists. In this document, a list of valid argument
       names is provided in the discussion of each widget. The
       names each have a global symbol defined that begins with
       XtN to help catch spelling errors. For example, XtNlabel is
       defined for the label resource of many widgets.
    5. For further information, see Section 2.9.2.2.
    6. When the argument list is set up, create the widget with
       the XtCreateManagedWidget function. For further
       information, see Section 2.2 and the X Toolkit Intrinsics -
       C Language Interface.
    7. If the widget has any callback routines, set by the
       XtNcallback argument or the XtAddCallback function, declare
       these routines within the application.
    8. After creating the initial widget hierarchy, windows must
       be created for each widget by calling XtRealizeWidget on
       the top level widget.
    9. Most applications now sit in a loop processing events using
       XtAppMainLoop , for example:
   10.
XtCreateManagedWidget(name, class, parent, args, num_args);
XtRealizeWidget(shell);
XtAppMainLoop(app_context);

   11. For information about this function, see the X Toolkit
       Intrinsics - C Language Interface.
   12. Link your application with libXaw (the Athena widgets),
       libXmu (miscellaneous utilities), libXt (the X Toolkit
       Intrinsics), libSM (Session Management), libICE
       (Inter-Client Exchange), libXext (the extension library
       needed for the shape extension code which allows rounded
       Command buttons), and libX11 (the core X library). The
       following provides a sample command line:
   13.
cc -o application application.c \-lXaw \-lXmu \-lXt \
\-lSM \-lICE \-lXext \-lX11

Changing Resource Values

   The Intrinsics support two methods of changing the default
   resource values; the resource manager, and an argument list
   passed into XtCreateWidget. While resources values will get
   updated no matter which method you use, the two methods provide
   slightly different functionality.

   Resource Manager
          This method picks up resource definitions described in
          Xlib - C Language Interface from many different
          locations at run time. The locations most important to
          the application programmer are the fallback resources
          and the app-defaults file, (see X Toolkit Intrinsics - C
          Language Interface for the complete list). Since these
          resource are loaded at run time, they can be overridden
          by the user, allowing an application to be customized to
          fit the particular needs of each individual user. These
          values can also be modified without the need to rebuild
          the application, allowing rapid prototyping of user
          interfaces. Application programmers should use resources
          in preference to hard-coded values whenever possible.

   Argument Lists
          The values passed into the widget at creation time via
          an argument list cannot be modified by the user, and
          allow no opportunity for customization. It is used to
          set resources that cannot be specified as strings (e.g.
          callback lists) or resources that should not be
          overridden (e.g. window depth) by the user.

Specifying Resources

   It is important for all X Toolkit application programmers to
   understand how to use the X Resource Manager to specify
   resources for widgets in an X application. This section will
   describe the most common methods used to specify these
   resources, and how to use the X Resource manager.

   Xrdb
          The xrdb utility may be used to load a file containing
          resources into the X server. Once the resources are
          loaded, the resources will affect any new applications
          started on the display that they were loaded onto.

   Application Defaults
          The application defaults (app-defaults) file (normally
          in /usr/lib/X11/app-defaults/classname) for an
          application is loaded whenever the application is
          started.

   The resource specification has two colon-separated parts, a
   name, and a value. The value is a string whose format is
   dependent on the resource specified by name. Name is
   constructed by appending a resource name to a full widget name.

   The full widget name is a list of the name of every ancestor of
   the desired widget separated by periods (.). Each widget also
   has a class associated with it. A class is a type of widget
   (e.g. Label or Scrollbar or Box). Notice that class names, by
   convention, begin with capital letters and instance names begin
   with lower case letters. The class of any widget may be used in
   place of its name in a resource specification. Here are a few
   examples:

   xman.form.button1
          This is a fully specified resource name, and will affect
          only widgets called button1 that are children of widgets
          called form that are children of applications named
          xman. (Note that while typically two widgets that are
          siblings will have different names, it is not
          prohibited.)

   Xman.Form.Command
          This will match any Command widget that is a child of a
          Form widget that is itself a child of an application of
          class Xman.

   Xman.Form.button1
          This is a mixed resource name with both widget names and
          classes specified.

   This syntax allows an application programmer to specify any
   widget in the widget tree. To match more than one widget (for
   example a user may want to make all Command buttons blue), use
   an asterisk (*) instead of a period. When an asterisk is used,
   any number of widgets (including zero) may exist between the
   two widget names. For example:

   Xman*Command
          This matches all Command widgets in the Xman
          application.

   Foo*button1
          This matches any widget in the Foo application that is
          named button1.

   The root of all application widget trees is the widget returned
   by XtAppInitialize. Even though this is actually an
   ApplicationShell widget, the toolkit replaces its widget class
   with the class name of the application. The name of this widget
   is either the name used to invoke the application (argv[0]) or
   the name of the application specified using the standard -name
   command line option supported by the Intrinsics.

   The last step in constructing the resource name is to append
   the name of the resource with either a period or asterisk to
   the full or partial widget name already constructed.

   *foreground:Blue
          Specifies that all widgets in all applications will have
          a foreground color of blue.

   Xman*borderWidth:10
          Specifies that all widgets in an application whose class
          is Xman will have a border width of 10 (pixels).

   xman.form.button1.label:Testing
          Specifies that a particular widget in the xman
          application will have a label named Testing.

   An exclamation point (!) in the first column of a line
   indicates that the rest of the line should be treated as a
   comment.

   Final Words

   The Resource manager is a powerful tool that can be used very
   effectively to customize X Toolkit applications at run time by
   either the application programmer or the user. Some final
   points to note:
     * An application programmer may add new resources to their
       application. These resources are associated with the global
       application, and not any particular widget. The X Toolkit
       function used for adding the application resources is
       XtGetApplicationResources.
     * Be careful when creating resource files. Since widgets will
       ignore resources that they do not understand, any spelling
       errors will cause a resource to have no effect.
     * Only one resource line will match any given resource. There
       is a set of precedence rules, which take the following
       general stance.
     *
          + More specific overrides less specific, thus period
            always overrides asterisk.
          + Names on the left are more specific and override names
            on the right.
          + When resource specifications are exactly the same,
            user defaults will override program defaults.

   For a complete explanation of the rules of precedence, and
   other specific topics see X Toolkit Intrinsics - C Language
   Interface and Xlib - C Language Interface.

Creating Argument Lists

   To set up an argument list for the inline specification of
   widget attributes, you may use any of the four approaches
   discussed in this section. Each resource name has a global
   symbol associated with it. This global symbol has the form
   XtNresource name. For example, the symbol for ``foreground'' is
   XtNforeground. For further information, see the X Toolkit
   Intrinsics - C Language Interface.

   Argument are specified by using the following structure:



typedef struct {
        String name;
        XtArgVal value;
} Arg, *ArgList;

   The first approach is to statically initialize the argument
   list. For example:



static Arg arglist[] = {
        {XtNwidth, (XtArgVal) 400},
        {XtNheight, (XtArgVal) 300},
};

   This approach is convenient for lists that do not need to be
   computed at runtime and makes adding or deleting new elements
   easy. The XtNumber macro is used to compute the number of
   elements in the argument list, preventing simple programming
   errors:

XtCreateWidget(name, class, parent, arglist, XtNumber(arglist));

   The second approach is to use the XtSetArg macro. For example:



Arg arglist[10];
XtSetArg(arglist[1], XtNwidth, 400);
XtSetArg(arglist[2], XtNheight, 300);

   To make it easier to insert and delete entries, you also can
   use a variable index:



Arg arglist[10];
Cardinal i=0;
XtSetArg(arglist[i], XtNwidth,  400);       i++;
XtSetArg(arglist[i], XtNheight, 300);       i++;

   The i variable can then be used as the argument list count in
   the widget create function. In this example, XtNumber would
   return 10, not 2, and therefore is not useful. You should not
   use auto-increment or auto-decrement within the first argument
   to XtSetArg . As it is currently implemented, XtSetArg is a
   macro that dereferences the first argument twice.

   The third approach is to individually set the elements of the
   argument list array:



Arg arglist[10];
arglist[0].name  = XtNwidth;
arglist[0].value = (XtArgVal) 400;
arglist[1].name  = XtNheight;
arglist[1].value = (XtArgVal) 300;

   Note that in this example, as in the previous example, XtNumber
   would return 10, not 2, and therefore would not be useful.

   The fourth approach is to use a mixture of the first and third
   approaches: you can statically define the argument list but
   modify some entries at runtime. For example:



static Arg arglist[] = {
        {XtNwidth, (XtArgVal) 400},
        {XtNheight, (XtArgVal) NULL},
};
arglist[1].value = (XtArgVal) 300;

   In this example, XtNumber can be used, as in the first
   approach, for easier code maintenance.

Example Programs

   The best way to understand how to use any programming library
   is by trying some simple examples. A collection of example
   programs that introduces each of the widgets in that Athena
   widget set, as well as many important toolkit programming
   concepts, is available in the X11R6 release as distributed by
   the X Consortium. It can be found in the distribution directory
   contrib/examples/mit/Xaw, but see your site administrator for
   the exact location of these files on your system. See the
   README file from that directory for a guide to the examples.

Chapter 3. Simple Widgets

   Table of Contents

   Command Widget

        Resources
        Command Actions

   Grip Widget

        Resources
        Grip Actions

   Label Widget

        Resources

   List Widget

        Resources
        List Actions
        List Callbacks
        Changing the List
        Highlighting an Item
        Unhighlighting an Item
        Retrieving the Currently Selected Item
        Restrictions

   Panner Widget

        Resources
        Panner Actions
        Panner Callbacks

   Repeater Widget

        Resources
        Repeater Actions

   Scrollbar Widget

        Resources
        Scrollbar Actions
        Scrollbar Callbacks
        Convenience Routines
        Setting Float Resources

   Simple Widget

        Resources

   StripChart Widget

        Resources
        Getting the StripChart Value

   Toggle Widget

        Resources
        Toggle Actions
        Toggle Actions_b
        Radio Groups
        Convenience Routines

   Each of these widgets performs a specific user interface
   function. They are simple because they cannot have widget
   children\(emthey may only be used as leaves of the widget tree.
   These widgets display information or take user input.

   Command
          A push button that, when selected, may cause a specific
          action to take place. This widget can display a
          multi-line string or a bitmap or pixmap image.

   Grip
          A rectangle that, when selected, will cause an action to
          take place.

   Label
          A rectangle that can display a multi-line string or a
          bitmap or pixmap image.

   List
          A list of text strings presented in row column format
          that may be individually selected. When an element is
          selected an action may take place.

   Panner
          A rectangular area containing a slider that may be moved
          in two dimensions. Notification of movement may be
          continuous or discrete.

   Repeater
          A push button that triggers an action at an increasing
          rate when selected. This widget can display a multi-line
          string or a bitmap or pixmap image.

   Scrollbar
          A rectangular area containing a thumb that when slid
          along one dimension may cause a specific action to take
          place. The Scrollbar may be oriented horizontally or
          vertically.

   Simple
          The base class for most of the simple widgets. Provides
          a rectangular area with a settable mouse cursor and
          special border.

   StripChart
          A real time data graph that will automatically update
          and scroll.

   Toggle
          A push button that contains state information. Toggles
          may also be used as "radio buttons" to implement a "one
          of many" or "zero or one of many" group of buttons. This
          widget can display a multi-line string or a bitmap or
          pixmap image.

Command Widget




Application header file <X11/Xaw/Command.h>

Class header file       <X11/Xaw/CommandP.h>

Class   commandWidgetClass

Class Name      Command

Superclass      Label


   The Command widget is an area, often rectangular, that contains
   text or a graphical image. Command widgets are often referred
   to as ``push buttons.'' When the pointer is over a Command
   widget, the widget becomes highlighted by drawing a rectangle
   around its perimeter. This highlighting indicates that the
   widget is ready for selection. When mouse button 1 is pressed,
   the Command widget indicates that it has been selected by
   reversing its foreground and background colors. When the mouse
   button is released, the Command widget's notify action is
   invoked, calling all functions on its callback list. If the
   pointer is moved off of the widget before the pointer button is
   released, the widget reverts to its normal foreground and
   background colors, and releasing the pointer button has no
   effect. This behavior allows the user to cancel an action.

Resources

   When creating a Command widget instance, the following
   resources are retrieved from the argument list or from the
   resource database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   bitmap Bitmap Pixmap   None
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   callback Callback XtCallbackList   NULL
   colormap Colormap Colormap   Parent's Colormap
   cornerRoundPercent CornerRoundPercent Dimension   25
   cursor Cursor Cursor   None
   cursorName Cursor String   NULL
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   encoding Encoding UnsignedChar   XawTextEncoding8bit
   font Font XFontStruct   XtDefaultFont
   foreground Foreground Pixel   XtDefaultForeground
   height Height Dimension A graphic height + 2 * internalHeight
   highlightThickness Thickness Dimension A 2 (0 if Shaped)
   insensitiveBorder Insensitive Pixmap   GreyPixmap
   internalHeight Height Dimension   2
   internalWidth Width Dimension   4
   international International Boolean C False
   justify Justify Justify   XtJustifyCenter (center)
   label Label String   name of widget
   leftBitmap LeftBitmap Bitmap   None
   mappedWhenManaged MappedWhenManaged Boolean   True
   pointerColor Foreground Pixel   XtDefaultForeground
   pointerColorBackground Background Pixel   XtDefaultBackground
   resize Resize Boolean   True
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   shapeStyle ShapeStyle ShapeStyle   Rectangle
   translations Translations TranslationTable   See below
   width Width Dimension A graphic width + 2 * internalWidth
   x Position Position   0
   y Position Position   0
   _

   \" Resource Descriptions

Command Actions

   The Command widget supports the following actions:
     * Switching the button's interior between the foreground and
       background colors with set, unset, and reset.
     * Processing application callbacks with notify
     * Switching the internal border between highlighted and
       unhighlighted states with highlight and unhighlight

   The following are the default translation bindings used by the
   Command widget:



        <EnterWindow>:  highlight(\|)
        <LeaveWindow>:  reset(\|)
        <Btn1Down>:     set(\|)
        <Btn1Up>:       notify(\|) unset(\|)

   The full list of actions supported by Command is:

   highlight(condition)
          Displays the internal highlight border in the color
          (foreground or background ) that contrasts with the
          interior color of the Command widget. The conditions
          WhenUnset and Always are understood by this action
          procedure. If no argument is passed, WhenUnset is
          assumed.

   unhighlight(\|)
          Displays the internal highlight border in the color
          (foreground or background ) that matches the interior
          color of the Command widget.

   set(\|)
          Enters the set state, in which notify is possible. This
          action causes the button to display its interior in the
          foreground color. The label or bitmap is displayed in
          the background color.

   unset(\|)
          Cancels the set state and displays the interior of the
          button in the background color. The label or bitmap is
          displayed in the foreground color.

   reset(\|)
          Cancels any set or highlight and displays the interior
          of the button in the background color, with the label or
          bitmap displayed in the foreground color.

   notify(\|)
          When the button is in the set state this action calls
          all functions in the callback list named by the callback
          resource. The value of the call_data argument passed to
          these functions is undefined.

   A very common alternative to registering callbacks is to
   augment a Command's translations with an action performing the
   desired function. This often takes the form of:



*Myapp*save.translations: #augment <Btn1Down>,<Btn1Up>: Save()

   When a bitmap of depth greater that one (1) is specified the
   set(), unset(), and reset() actions have no effect, since there
   are no foreground and background colors used in a multi-plane
   pixmap.

Grip Widget




Application header file <X11/Xaw/Grip.h>

Class header file       <X11/Xaw/GripP.h>

Class   gripWidgetClass

Class Name      Grip

Superclass      Simple


   The Grip widget provides a small rectangular region in which
   user input events (such as ButtonPress or ButtonRelease) may be
   handled. The most common use for the Grip widget is as an
   attachment point for visually repositioning an object, such as
   the pane border in a Paned widget.

Resources

   When creating a Grip widget instance, the following resources
   are retrieved from the argument list or from the resource
   database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   0
   callback Callback Callback   NULL
   colormap Colormap Colormap   Parent's Colormap
   cursor Cursor Cursor   None
   cursorName Cursor String   NULL
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   foreground Foreground Pixel   XtDefaultForeground
   height Height Dimension   8
   insensitiveBorder Insensitive Pixmap   GreyPixmap
   international International Boolean C False
   mappedWhenManaged MappedWhenManaged Boolean   True
   pointerColor Foreground Pixel   XtDefaultForeground
   pointerColorBackground Background Pixel   XtDefaultBackground
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   translations Translations TranslationTable   NULL
   width Width Dimension   8
   x Position Position   0
   y Position Position   0

   callback
          All routines on this list are called whenever the
          GripAction action routine is invoked. The call_data
          contains all information passed to the action routine. A
          detailed description is given below in the Grip Actions
          section.

   foreground
          A pixel value which indexes the widget's colormap to
          derive the color used to flood fill the entire Grip
          widget.

Grip Actions

   The Grip widget does not declare any default event translation
   bindings, but it does declare a single action routine named
   GripAction. The client specifies an arbitrary event translation
   table, optionally giving parameters to the GripAction routine.

   The GripAction routine executes the callbacks on the callback
   list, passing as call_data a pointer to a XawGripCallData
   structure, defined in the Grip widget's application header
   file.






typedef struct _XawGripCallData {
        XEvent *event;
        String *params;
        Cardinal num_params;
} XawGripCallDataRec, *XawGripCallData,
  GripCallDataRec, *GripCallData; /* supported for R4 compatibility */





   In this structure, the event is a pointer to the input event
   that triggered the action. params and num_params give the
   string parameters specified in the translation table for the
   particular event binding.

   The following is an example of a translation table that uses
   the GripAction:




        <Btn1Down>:     GripAction(press)
        <Btn1Motion>:   GripAction(move)
        <Btn1Up>:       GripAction(release)


   For a complete description of the format of translation tables,
   see the X Toolkit Intrinsics - C Language Interface.

Label Widget




Application header file <X11/Xaw/Label.h>

Class header file       <X11/Xaw/LabelP.h>

Class   labelWidgetClass

Class Name      Label

Superclass      Simple


   A Label widget holds a graphic displayed within a rectangular
   region of the screen. The graphic may be a text string
   containing multiple lines of characters in an 8 bit or 16 bit
   character set (to be displayed with a font), or in a multi-byte
   encoding (for use with a fontset). The graphic may also be a
   bitmap or pixmap. The Label widget will allow its graphic to be
   left, right, or center justified. Normally, this widget can be
   neither selected nor directly edited by the user. It is
   intended for use as an output device only.

Resources

   When creating a Label widget instance, the following resources
   are retrieved from the argument list or from the resource
   database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   bitmap Bitmap Pixmap   None
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   colormap Colormap Colormap   Parent's Colormap
   cursor Cursor Cursor   None
   cursorName Cursor String   NULL
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   encoding Encoding UnsignedChar   XawTextEncoding8bit
   font Font XFontStruct   XtDefaultFont
   fontSet FontSet XFontSet   XtDefaultFontSet
   foreground Foreground Pixel   XtDefaultForeground
   height Height Dimension A graphic height + 2 * internalHeight
   insensitiveBorder Insensitive Pixmap   GreyPixmap
   internalHeight Height Dimension   2
   internalWidth Width Dimension   4
   international International Boolean C False
   justify Justify Justify   XtJustifyCenter (center)
   label Label String   name of widget
   leftBitmap LeftBitmap Bitmap   None
   mappedWhenManaged MappedWhenManaged Boolean   True
   pointerColor Foreground Pixel   XtDefaultForeground
   pointerColorBackground Background Pixel   XtDefaultBackground
   resize Resize Boolean   True
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   translations Translations TranslationTable   See above
   width Width Dimension A graphic width + 2 * internalWidth
   x Position Position   0
   y Position Position   0

List Widget




Application header file <X11/Xaw/List.h>

Class header file       <X11/Xaw/ListP.h>

Class   listWidgetClass

Class Name      List

Superclass      Simple


   The List widget contains a list of strings formatted into rows
   and columns. When one of the strings is selected, it is
   highlighted, and the List widget's Notify action is invoked,
   calling all routines on its callback list. Only one string may
   be selected at a time.

Resources

   When creating a List widget instance, the following resources
   are retrieved from the argument list or from the resource
   database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   callback Callback Callback   NULL
   colormap Colormap Colormap   Parent's Colormap
   columnSpacing Spacing Dimension   6
   cursor Cursor Cursor   XC_left_ptr
   cursorName Cursor String   NULL
   defaultColumns Columns int   2
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   font Font FontStruct   XtDefaultFont
   fontSet FontSet XFontSet   XtDefaultFontSet
   forceColumns Columns Boolean   False
   foreground Foreground Pixel   XtDefaultForeground
   height Height Dimension A Enough space to contain the list
   insensitiveBorder Insensitive Pixmap   GreyPixmap
   internalHeight Height Dimension   2
   internalWidth Width Dimension   4
   international International Boolean C False
   list List Pointer   name of widget
   longest Longest int A 0
   mappedWhenManaged MappedWhenManaged Boolean   True
   numberStrings NumberStrings int A computed for NULL terminated
   list
   pasteBuffer Boolean Boolean   False
   pointerColor Foreground Pixel   XtDefaultForeground
   pointerColorBackground Background Pixel   XtDefaultBackground
   rowSpacing Spacing Dimension   2
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   translations Translations TranslationTable   See below
   verticalList Boolean Boolean   False
   width Width Dimension A Enough space to contain the list
   x Position Position   0
   y Position Position   0
   _

   callback
          All functions on this list are called whenever the
          notify action is invoked. The call_data argument
          contains information about the element selected and is
          described in detail in the List Callbacks section.

   columnSpacing

   rowSpacing
          The amount of space, in pixels, between each of the rows
          and columns in the list.

   defaultColumns
          The default number of columns. This value is used when
          neither the width nor the height of the List widget is
          specified or when forceColumns is True.

   font
          The text font to use when displaying the list, when the
          international resource is false.

   fontSet
          The text font set to use when displaying the list, when
          the international resource is true.

   forceColumns
          Forces the default number of columns to be used
          regardless of the List widget's current size.

   foreground
          A pixel value which indexes the widget's colormap to
          derive the color used to paint the text of the list
          elements.

   \fPinternalHeight\fP

   \fPinternalWidth\fP
          The margin, in pixels, between the edges of the list and
          the corresponding edge of the List widget's window.

   list
          An array of text strings displayed in the List widget.
          If numberStrings is zero (the default) then the list
          must be NULL terminated. If a value is not specified for
          the list, then numberStrings is set to 1, and the name
          of the widget is used as the list, and longest is set to
          the length of the name of the widget. The list is used
          in place, and must be available to the List widget for
          the lifetime of this widget, or until it is changed with
          XtSetValues or XawListChange.

   longest
          Specifies the width, in pixels, of the longest string in
          the current list. The List widget will compute this
          value if zero (the default) is specified. If this
          resource is set by hand, entries longer than this will
          be clipped to fit.

   numberStrings
          The number of strings in the current list. If a value of
          zero (the default) is specified, the List widget will
          compute it. When computing the number of strings the
          List widget assumes that the list is NULL terminated.

   pasteBuffer
          If this resource is set to True then the name of the
          currently selected list element will be put into
          CUT_BUFFER_0.

   verticalList
          If this resource is set to True then the list elements
          will be presented in column major order.

List Actions

   The List widget supports the following actions:
     * Highlighting and unhighlighting the list element under the
       pointer with Set and Unset
     * Processing application callbacks with Notify

   The following is the default translation table used by the List
   Widget:



<Btn1Down>,<Btn1Up>:    Set(\|) Notify(\|)


   The full list of actions supported by List widget is:

   Set(\|)
          Sets the list element that is currently under the
          pointer. To inform the user that this element is
          currently set, it is drawn with foreground and
          background colors reversed. If this action is called
          when there is no list element under the cursor, the
          currently set element will be unset.

   Unset(\|)
          Cancels the set state of the element under the pointer,
          and redraws it with normal foreground and background
          colors.

   Notify(\|)
          Calls all callbacks on the List widget's callback list.
          Information about the currently selected list element is
          passed in the call_data argument (see List Callbacks
          below).

List Callbacks

   All procedures on the List widget's callback list will have a
   XawListReturnStruct passed to them as call_data. The structure
   is defined in the List widget's application header file.



typedef struct _XawListReturnStruct {
        String string;  /* string shown in the list. */
        int list_index; /* index of the item selected. */
} XawListReturnStruct;



Note

   The list_index item used to be called simply index.
   Unfortunately, this name collided with a global name defined on
   some operating systems, and had to be changed.

Changing the List

   To change the list that is displayed, use XawListChange .
   void XawListChange( w,
                       list,
                       longest,
                       resize);
   Widget w;
   String* list;
   intnitems, longest;
   Boolean resize;

   w
          Specifies the List widget.

   list
          Specifies the new list for the List widget to display.

   nitems
          Specifies the number of items in the list. If a value
          less than 1 is specified, list must be NULL terminated,
          and the number of items will be calculated by the List
          widget.

   longest
          Specifies the length of the longest item in the list in
          pixels. If a value less than 1 is specified, the List
          widget will calculate the value.

   resize
          Specifies a Boolean value that if True indicates that
          the List widget should try to resize itself after making
          the change. The constraints of the List widget's parent
          are always enforced, regardless of the value specified
          here.

   XawListChange will unset all list elements that are currently
   set before the list is actually changed. The list is used in
   place, and must remain usable for the lifetime of the List
   widget, or until list has been changed again with this function
   or with XtSetValues.

Highlighting an Item

   To highlight an item in the list, use XawListHighlight .
   void XawListHighlight( w,
                          item);
   Widget w;
   int item;

   w
          Specifies the List widget.

   item
          Specifies an index into the current list that indicates
          the item to be highlighted.

   Only one item can be highlighted at a time. If an item is
   already highlighted when XawListHighlight is called, the
   highlighted item is unhighlighted before the new item is
   highlighted.

Unhighlighting an Item

   To unhighlight the currently highlighted item in the list, use
   XawListUnhighlight .
   void XawListUnhighlight( w);
   Widget w;

   w
          Specifies the List widget.

Retrieving the Currently Selected Item

   To retrieve the list element that is currently set, use
   XawListShowCurrent .
   XawListReturnStruct *XawListShowCurrent( w);
   Widget w;

   w
          Specifies the List widget.

   XawListShowCurrent returns a pointer to an XawListReturnStruct
   structure, containing the currently highlighted item. If the
   value of the index member is XAW_LIST_NONE, the string member
   is undefined, and no item is currently selected.

Restrictions

   Many programmers create a ``scrolled list'' by putting a List
   widget with many entries as a child of a Viewport widget. The
   List continues to create a window as big as its contents, but
   that big window is only visible where it intersects the parent
   Viewport's window. (I.e., it is ``clipped.'')

   While this is a useful technique, there is a serious drawback.
   X does not support windows above 32,767 pixels in width or
   height, but this height limit will be exceeded by a List's
   window when the List has many entries (i.e., with a 12 point
   font, about 3000 entries would be too many.)

Panner Widget




Application header file <X11/Xaw/Panner.h>

Class header file       <X11/Xaw/PannerP.h>

Class           pannerWidgetClass

Class Name      Panner

Superclass      Simple


   A Panner widget is a rectangle, called the ``canvas,'' on which
   another rectangle, the ``slider,'' moves in two dimensions. It
   is often used with a Porthole widget to move, or ``scroll,'' a
   third widget in two dimensions, in which case the slider's size
   and position gives feedback as to what portion of the third
   widget is visible.

   The slider may be scrolled around the canvas by pressing,
   dragging, and releasing Button1; the default translation also
   enables scrolling via arrow keys and some other keys. While
   scrolling is in progress, the application receives notification
   through callback procedures. Notification may be done either
   continuously whenever the slider moves or discretely whenever
   the slider has been given a new location.

Resources

   When creating a Panner widget instance, the following resources
   are retrieved from the argument list or from the resource
   database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   allowOff AllowOff Boolean   False
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   backgroundStipple BackgroundStipple String   NULL
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   canvasHeight CanvasHeight Dimension   0
   canvasWidth CanvasWidth Dimension   0
   colormap Colormap Colormap   Parent's Colormap
   cursor Cursor Cursor   None
   cursorName Cursor String   NULL
   defaultScale DefaultScale Dimension   8
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   foreground Foreground Pixel   XtDefaultForeground
   height Height Dimension A depends on orientation
   internalSpace InternalSpace Dimension   4
   international International Boolean C False
   lineWidth LineWidth Dimension   0
   mappedWhenManaged MappedWhenManaged Boolean   True
   pointerColor Foreground Pixel   XtDefaultForeground
   pointerColorBackground Background Pixel   XtDefaultBackground
   reportCallback ReportCallback Callback   NULL
   resize Resize Boolean   True
   rubberBand RubberBand Boolean   False
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   shadowColor ShadowColor Pixel   XtDefaultForeground
   shadowThickness ShadowThickness Dimension   2
   sliderX SliderX Position   0
   sliderY SliderY Position   0
   sliderHeight SliderHeight Dimension   0
   sliderWidth SliderWidth Dimension   0
   translations Translations TranslationTable   See below
   width Width Dimension A depends on orientation
   x Position Position   0
   y Position Position   0

   allowOff
          Whether to allow the edges of the slider to go off the
          edges of the canvas.

   backgroundStipple
          The name of a bitmap pattern to be used as the
          background for the area representing the canvas.

   canvasHeight

   canvasWidth
          The size of the canvas.

   defaultScale
          The percentage size that the Panner widget should have
          relative to the size of the canvas.

   foreground
          A pixel value which indexes the widget's colormap to
          derive the color used to draw the slider.

   internalSpace
          The width of internal border in pixels between a slider
          representing the full size of the canvas and the edge of
          the Panner widget.

   lineWidth
          The width of the lines in the rubberbanding rectangle
          when rubberbanding is in effect instead of continuous
          scrolling. The default is 0.

   reportCallback
          All functions on this callback list are called when the
          notify action is invoked. See the Panner Actions section
          for details.

   resize
          Whether or not to resize the panner whenever the canvas
          size is changed so that the defaultScale is maintained.

   rubberBand
          Whether or not scrolling should be discrete (only moving
          a rubberbanded rectangle until the scrolling is done) or
          continuous (moving the slider itself). This controls
          whether or not the move action procedure also invokes
          the notify action procedure.

   shadowColor
          The color of the shadow underneath the slider.

   shadowThickness
          The width of the shadow underneath the slider.

   sliderX

   sliderY
          The location of the slider in the coordinates of the
          canvas.

   sliderHeight

   sliderWidth
          The size of the slider.

Panner Actions

   The actions supported by the Panner widget are:

   start()
          This action begins movement of the slider.

   stop()
          This action ends movement of the slider.

   abort()
          This action ends movement of the slider and restores it
          to the position it held when the start action was
          invoked.

   move()
          This action moves the outline of the slider (if the
          rubberBand resource is True) or the slider itself (by
          invoking the notify action procedure).

   page(xamount,yamount)
          This action moves the slider by the specified amounts.
          The format for the amounts is a signed or unsigned
          floating-point number (e.g., +1.0 or \-.5) followed by
          either p indicating pages (slider sizes), or c
          indicating canvas sizes. Thus, page(+0,+.5p) represents
          vertical movement down one-half the height of the slider
          and page(0,0) represents moving to the upper left corner
          of the canvas.

   notify()
          This action informs the application of the slider's
          current position by invoking the reportCallback
          functions registered by the application.

   set(what,value)
          This action changes the behavior of the Panner. The what
          argument must currently be the string rubberband and
          controls the value of the rubberBand resource. The value
          argument may have one of the values on, off, or toggle.

   The default bindings for Panner are:


        <Btn1Down>:     start(\|)
        <Btn1Motion>:   move(\|)
        <Btn1Up>:       notify(\|) stop(\|)
        <Btn2Down>:     abort(\|)
        <Key>KP_Enter:  set(rubberband,toggle)
        <Key>space:     page(+1p,+1p)
        <Key>Delete:    page(\-1p,\-1p)
        <Key>BackSpace: page(\-1p,\-1p)
        <Key>Left:      page(\-.5p,+0)
        <Key>Right:     page(+.5p,+0)
        <Key>Up:        page(+0,\-.5p)
        <Key>Down:      page(+0,+.5p)
        <Key>Home:      page(0,0)

Panner Callbacks

   The functions registered on the reportCallback list are invoked
   by the notify action as follows:
   void ReportProc( panner,
                    client_data,
                    report);
   Widget panner;
   XtPointer client_data;
   XtPointer report;

   panner
          Specifies the Panner widget.

   panner
          Specifies the client data.

   panner
          Specifies a pointer to an XawPannerReport structure
          containing the location and size of the slider and the
          size of the canvas.

Repeater Widget




Application header file <X11/Xaw/Repeater.h>

Class header file       <X11/Xaw/RepeaterP.h>

Class   repeaterWidgetClass

Class Name      Repeater

Superclass      Command


   The Repeater widget is a subclass of the Command widget; see
   the Command documentation for details. The difference is that
   the Repeater can call its registered callbacks repeatedly, at
   an increasing rate. The default translation does so for the
   duration the user holds down pointer button 1 while the pointer
   is on the Repeater.

Resources

   When creating a Repeater widget instance, the following
   resources are retrieved from the argument list or from the
   resource database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   bitmap Bitmap Pixmap   None
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   callback Callback XtCallbackList   NULL
   colormap Colormap Colormap   Parent's Colormap
   cornerRoundPercent CornerRoundPercent Dimension   25
   cursor Cursor Cursor   None
   cursorName Cursor String   NULL
   decay Decay Int   5
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   encoding Encoding UnsignedChar   XawTextEncoding8bit
   flash Boolean Boolean   False
   font Font XFontStruct   XtDefaultFont
   fontSet FontSet XFontSet   XtDefaultFontSet
   foreground Foreground Pixel   XtDefaultForeground
   height Height Dimension A graphic height + 2 * internalHeight
   highlightThickness Thickness Dimension A 2 (0 if Shaped)
   initialDelay Delay Int   200
   insensitiveBorder Insensitive Pixmap   GreyPixmap
   internalHeight Height Dimension   2
   internalWidth Width Dimension   4
   international International Boolean C False
   justify Justify Justify   XtJustifyCenter (center)
   label Label String   name of widget
   leftBitmap LeftBitmap Bitmap   None
   mappedWhenManaged MappedWhenManaged Boolean   True
   minimumDelay MinimumDelay Int   10
   pointerColor Foreground Pixel   XtDefaultForeground
   pointerColorBackground Background Pixel   XtDefaultBackground
   repeatDelay Delay Int   50
   resize Resize Boolean   True
   screen Screen Pointer R Parent's Screen
   sensitive Sensitive Boolean   True
   shapeStyle ShapeStyle ShapeStyle   Rectangle
   startCallback StartCallback Callback   NULL
   stopCallback StopCallback Callback   NULL
   translations Translations TranslationTable   See below
   width Width Dimension A graphic width + 2 * internalWidth
   x Position Position   0
   y Position Position   0

   \" Resource Descriptions

   decay
          The number of milliseconds that should be subtracted
          from each succeeding interval while the Repeater button
          is being held down until the interval has reached
          minimumDelay milliseconds.

   flash
          Whether or not to flash the Repeater button whenever the
          timer goes off.

   initialDelay
          The number of milliseconds between the beginning of the
          Repeater button being held down and the first invocation
          of the callback function.

   minimumDelay
          The minimum time between callbacks in milliseconds.

   repeatDelay
          The number of milliseconds between each callback after
          the first (minus an increasing number of decays).

   startCallback
          The list of functions to invoke by the start action
          (typically when the Repeater button is first pressed).
          The callback data parameter is set to NULL.

   stopCallback
          The list of functions to invoke by the stop action
          (typically when the Repeater button is released). The
          callback data parameter is set to NULL.

Repeater Actions

   The Repeater widget supports the following actions beyond those
   of the Command button:

   start()
          This invokes the functions on the startCallback and
          callback lists and sets a timer to go off in
          initialDelay milliseconds. The timer will cause the
          callback functions to be invoked with increasing
          frequency until the stop action occurs.

   stop()
          This invokes the functions on the stopCallback list and
          prevents any further timers from occuring until the next
          start action.

   The following are the default translation bindings used by the
   Repeater widget:



        <EnterWindow>:  highlight(\|)
        <LeaveWindow>:  unhighlight(\|)
        <Btn1Down>:     set(\|) start(\|)
        <Btn1Up>:       stop(\|) unset(\|)

Scrollbar Widget

Application header file     <X11/Xaw/Scrollbar.h>
Class header file           <X11/Xaw/ScrollbarP.h>
Class                       scrollbarWidgetClass
Class Name                  Scrollbar
Superclass                  Simple

   A Scrollbar widget is a rectangle, called the ``canvas,'' on
   which another rectangle, the ``thumb,'' moves in one dimension,
   either vertically or horizontally. A Scrollbar can be used
   alone, as a value generator, or it can be used within a
   composite widget (for example, a Viewport). When a Scrollbar is
   used to move, or ``scroll,'' the contents of another widget,
   the size and the position of the thumb usually give feedback as
   to what portion of the other widget's contents are visible.

   Each pointer button invokes a specific action. Pointer buttons
   1 and 3 do not move the thumb automatically. Instead, they
   return the pixel position of the cursor on the scroll region.
   When pointer button 2 is clicked, the thumb moves to the
   current pointer position. When pointer button 2 is held down
   and the pointer is moved, the thumb follows the pointer.

   The pointer cursor in the scroll region changes depending on
   the current action. When no pointer button is pressed, the
   cursor appears as a double-headed arrow that points in the
   direction that scrolling can occur. When pointer button 1 or 3
   is pressed, the cursor appears as a single-headed arrow that
   points in the logical direction that the thumb will move. When
   pointer button 2 is pressed, the cursor appears as an arrow
   that points to the top or the left of the thumb.

   When the user scrolls, the application receives notification
   through callback procedures. For both discrete scrolling
   actions, the callback returns the Scrollbar widget, the
   client_data, and the pixel position of the pointer when the
   button was released. For continuous scrolling, the callback
   routine returns the scroll bar widget, the client data, and the
   current relative position of the thumb. When the thumb is moved
   using pointer button 2, the callback procedure is invoked
   continuously. When either button 1 or 3 is pressed, the
   callback procedure is invoked only when the button is released
   and the client callback procedure is responsible for moving the
   thumb.

Resources

   When creating a Scrollbar widget instance, the following
   resources are retrieved from the argument list or from the
   resource database:
   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   colormap Colormap Colormap   parent's Colormap
   cursor Cursor Cursor   None
   cursorName Cursor String   NULL
   depth Depth int C parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   foreground Foreground Pixel   XtDefaultForeground
   height Height Dimension A depends on orientation
   insensitiveBorder Insensitive Pixmap   GreyPixmap
   international International Boolean C False
   jumpProc Callback XtCallbackList   NULL
   length Length Dimension   1
   mappedWhenManaged MappedWhenManaged Boolean   True
   minimumThumb MinimumThumb Dimension   7
   orientation Orientation Orientation   XtorientVertical
   (vertical)
   pointerColor Foreground Pixel   XtDefaultForeground
   pointerColorBackground Background Pixel   XtDefaultBackground
   screen Screen Screen R parent's Screen
   scrollDCursor Cursor Cursor   XC_sb_down_arrow
   scrollHCursor Cursor Cursor   XC_sb_h_double_arrow
   scrollLCursor Cursor Cursor   XC_sb_left_arrow
   scrollProc Callback XtCallbackList   NULL
   scrollRCursor Cursor Cursor   XC_sb_right_arrow
   scrollUCursor Cursor Cursor   XC_sb_up_arrow
   scrollVCursor Cursor Cursor   XC_sb_v_arrow
   sensitive Sensitive Boolean   True
   shown Shown Float   0.0
   thickness Thickness Dimension   14
   thumb Thumb Bitmap   GreyPixmap
   thumbProc Callback XtCallbackList   NULL
   topOfThumb TopOfThumb Float   0.0
   translations Translations TranslationTable   See below
   width Width Dimension A depends on orientation
   x Position Position   0
   y Position Position   0

   foreground
          A pixel value which indexes the widget's colormap to
          derive the color used to draw the thumb.

   jumpProc
          All functions on this callback list are called when the
          NotifyThumb action is invoked. See the Scrollbar Actions
          section for details.

   length
          The height of a vertical scrollbar or the width of a
          horizontal scrollbar.

   minimumThumb
          The smallest size, in pixels, to which the thumb can
          shrink.

   orientation
          The orientation is the direction that the thumb will be
          allowed to move. This value can be either
          XtorientVertical or XtorientHorizontal.

   scrollDCursor
          This cursor is used when scrolling backward in a
          vertical scrollbar.

   scrollHCursor
          This cursor is used when a horizontal scrollbar is
          inactive.

   scrollLCursor
          This cursor is used when scrolling forward in a
          horizontal scrollbar.

   scrollProc
          All functions on this callback list may be called when
          the NotifyScroll action is invoked. See the \fBScrollbar
          Actions\fP section for details.

   scrollRCursor
          This cursor is used when scrolling backward in a
          horizontal scrollbar, or when thumbing a vertical
          scrollbar.

   scrollUCursor
          This cursor is used when scrolling forward in a vertical
          scrollbar, or when thumbing a horizontal scrollbar.

   scrollVCursor
          This cursor is used when a vertical scrollbar is
          inactive.

   shown
          This is the size of the thumb, expressed as a percentage
          (0.0 - 1.0) of the length of the scrollbar.

   thickness
          The width of a vertical scrollbar or the height of a
          horizontal scrollbar.

   thumb
          This pixmap is used to tile (or stipple) the thumb of
          the scrollbar. If no tiling is desired, then set this
          resource to None. This resource will accept either a
          bitmap or a pixmap that is the same depth as the window.
          The resource converter for this resource constructs
          bitmaps from the contents of files. (See Converting
          Bitmaps for details.)

   topOfThumb
          The location of the top of the thumb, as a percentage
          (0.0 - 1.0) of the length of the scrollbar. This
          resource was called top in previous versions of the
          Athena widget set. The name collided with the a Form
          widget constraint resource, and had to be changed.

Scrollbar Actions

   The actions supported by the Scrollbar widget are:

   StartScroll(value)
          The possible values are Forward, Backward, or
          Continuous. This must be the first action to begin a new
          movement.

   NotifyScroll(value)
          The possible values are Proportional or FullLength. If
          the argument to StartScroll was Forward or Backward,
          NotifyScroll executes the scrollProc callbacks and
          passes either; the position of the pointer, if value is
          Proportional, or the full length of the scroll bar, if
          value is FullLength. If the argument to StartScroll was
          Continuous, NotifyScroll returns without executing any
          callbacks.

   EndScroll(\^)
          This must be the last action after a movement is
          complete.

   MoveThumb(\^)
          Repositions the Scrollbar's thumb to the current pointer
          location.

   NotifyThumb(\^)\
          Calls the callbacks and passes the relative position of
          the pointer as a percentage of the scroll bar length.

   The default bindings for Scrollbar are:
     <Btn1Down>:     StartScroll(Forward)
     <Btn2Down>:     StartScroll(Continuous) MoveThumb(\|) NotifyThumb(\
|)
     <Btn3Down>:     StartScroll(Backward)
     <Btn2Motion>:     MoveThumb(\|) NotifyThumb(\|)
     <BtnUp>:     NotifyScroll(Proportional) EndScroll(\|)

   Examples of additional bindings a user might wish to specify in
   a resource file are:
*Scrollbar.Translations: \\
     ~Meta<Key>space:     StartScroll(Forward) NotifyScroll(FullLength)
\\n\\
      Meta<Key>space:     StartScroll(Backward) NotifyScroll(FullLength)
 \\n\\
          EndScroll(\|)

Scrollbar Callbacks

   There are two callback lists provided by the Scrollbar widget.
   The procedural interface for these functions is described here.

   The calling interface to the scrollProc callback procedure is:
   void ScrollProc( scrollbar,
                    client_data,
                    position);
   Widget scrollbar;
   XtPointer client_data;
   XtPointer position;

   scrollbar
          Specifies the Scrollbar widget.

   client_data
          Specifies the client data.

   position
          Specifies a pixel position in integer form.

   The scrollProc callback is used for incremental scrolling and
   is called by the NotifyScroll action. The position argument is
   a signed quantity and should be cast to an int when used. Using
   the default button bindings, button 1 returns a positive value,
   and button 3 returns a negative value. In both cases, the
   magnitude of the value is the distance of the pointer in pixels
   from the top (or left) of the Scrollbar. The value will never
   be greater than the length of the Scrollbar.

   The calling interface to the jumpProc callback procedure is:
   void JumpProc( scrollbar,
                  client_data,
                  percent_ptr);
   Widget scrollbar;
   XtPointer client_data;
   XtPointer percent_ptr;

   scrollbar
          Specifies the ID of the scroll bar widget.

   client_data
          Specifies the client data.

   percent_ptr
          Specifies the floating point position of the thumb (0.0
          \- 1.0).

   The jumpProc callback is used to implement smooth scrolling and
   is called by the NotifyThumb action. Percent_ptr must be cast
   to a pointer to float before use; i.e.
     float percent = *(float*)percent_ptr;

   With the default button bindings, button 2 moves the thumb
   interactively, and the jumpProc is called on each new position
   of the pointer, while the pointer button remains down. The
   value specified by percent_ptr is the current location of the
   thumb (from the top or left of the Scrollbar) expressed as a
   percentage of the length of the Scrollbar.

Convenience Routines

   To set the position and length of a Scrollbar thumb, use
   void XawScrollbarSetThumb( w,
                              top,
                              shown);
   Widget w;
   float top;
   float shown;

   w
          Specifies the Scrollbar widget.

   top
          Specifies the position of the top of the thumb as a
          fraction of the length of the Scrollbar.

   shown
          Specifies the length of the thumb as a fraction of the
          total length of the Scrollbar.

   XawScrollbarThumb moves the visible thumb to a new position
   (0.0 \- 1.0) and length (0.0 \- 1.0). Either the top or shown
   arguments can be specified as \-1.0, in which case the current
   value is left unchanged. Values greater than 1.0 are truncated
   to 1.0.

   If called from jumpProc, XawScrollbarSetThumb has no effect.

Setting Float Resources

   The shown and topOfThumb resources are of type float. These
   resources can be difficult to get into an argument list. The
   reason is that C performs an automatic cast of the float value
   to an integer value, usually truncating the important
   information. The following code fragment is one portable method
   of getting a float into an argument list.
     top = 0.5;
     if (sizeof(float) > sizeof(XtArgVal)) {
     /*
     \ * If a float is larger than an XtArgVal then pass this
     \ * resource value by reference.
     \ */
          XtSetArg(args[0], XtNshown, &top);
     }
     else {
     /*
     \ * Convince C not to perform an automatic conversion, which
     \ * would truncate 0.5 to 0.
     \ */
          XtArgVal * l_top = (XtArgVal *) &top;
          XtSetArg(args[0], XtNshown, *l_top);
     }

Simple Widget




Application Header file <Xaw/Simple.h>

Class Header file       <Xaw/SimpleP.h>

Class           simpleWidgetClass

Class Name      Simple

Superclass      Core


   The Simple widget is not very useful by itself, as it has no
   semantics of its own. It main purpose is to be used as a common
   superclass for the other simple Athena widgets. This widget
   adds six resources to the resource list provided by the Core
   widget and its superclasses.

Resources

   When creating a Simple widget instance, the following resources
   are retrieved from the argument list or from the resource
   database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   colormap Colormap Colormap   Parent's Colormap
   cursor Cursor Cursor   None
   cursorName Cursor String   NULL
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   height Height Dimension   0
   insensitiveBorder Insensitive Pixmap   GreyPixmap
   international International Boolean C False
   mappedWhenManaged MappedWhenManaged Boolean   True
   pointerColor Foreground Pixel   XtDefaultForeground
   pointerColorBackground Background Pixel   XtDefaultBackground
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   translations Translations TranslationTable   NULL
   width Width Dimension   0
   x Position Position   0
   y Position Position   0

StripChart Widget




Application Header file <Xaw/StripChart.h>

Class Header file       <Xaw/StripCharP.h>

Class           stripChartWidgetClass

Class Name      StripChart

Superclass      Simple


   The StripChart widget is used to provide a roughly real time
   graphical chart of a single value. For example, it is used by
   the common client program xload to provide a graph of processor
   load. The StripChart reads data from an application, and
   updates the chart at the update interval specified.

Resources

   When creating a StripChart widget instance, the following
   resources are retrieved from the argument list or from the
   resource database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   colormap Colormap Colormap   Parent's Colormap
   cursor Cursor Cursor   None
   cursorName Cursor String   NULL
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   foreground Foreground Pixel   XtDefaultForeground
   getValue Callback XtCallbackList   NULL
   height Height Dimension   120
   highlight Foreground Pixel   XtDefaultForeground
   insensitiveBorder Insensitive Pixmap   GreyPixmap
   international International Boolean C False
   jumpScroll JumpScroll int A half the width of the widget
   mappedWhenManaged MappedWhenManaged Boolean   True
   minScale Scale int   1
   pointerColor Foreground Pixel   XtDefaultForeground
   pointerColorBackground Background Pixel   XtDefaultBackground
   screen Screen Pointer R Parent's Screen
   sensitive Sensitive Boolean   True
   translations Translations TranslationTable   NULL
   update Interval int   10
   width Width Dimension   120
   x Position Position   0
   y Position Position   0

   foreground
          A pixel value which indexes the widget's colormap to
          derive the color that will be used to draw the graph.

   getValue
          A list of callback functions to call every update
          seconds. This list should contain one function, which
          returns the value to be graphed by the StripChart
          widget. The following section describes the procedural
          interface. Behavior when this list has more than one
          function is undefined.

   highlight
          A pixel value which indexes the widget's colormap to
          derive the color that will be used to draw the scale
          lines on the graph.

   jumpScroll
          When the graph reaches the right edge of the window it
          must be scrolled to the left. This resource specifies
          the number of pixels it will jump. Smooth scrolling can
          be achieved by setting this resource to 1.

   minScale
          The minimum scale for the graph. The number of divisions
          on the graph will always be greater than or equal to
          this value.

   update
          The number of seconds between graph updates. Each update
          is represented on the graph as a 1 pixel wide line.
          Every update seconds the getValue procedure will be used
          to get a new graph point, and this point will be added
          to the right end of the StripChart.

Getting the StripChart Value

   The StripChart widget will call the application routine passed
   to it as the getValue callback function every update seconds to
   obtain another point for the StripChart graph.

   The calling interface for the getValue callback is:
   void(*getValueProc)( w,
                        client_data,
                        value);
   Widget w;
   XtPointer client_data;
   XtPointer value;

   w
          Specifies the StripChart widget.

   client_data
          Specifies the client data.

   value
          Returns a pointer to a double. The application should
          set the address pointed to by this argument to a double
          containing the value to be graphed on the StripChart.

   This function is used by the StripChart to call an application
   routine. The routine will pass the value to be graphed back to
   the the StripChart in the value field of this routine.

Toggle Widget

Application Header file     <Xaw/Toggle.h>
Class Header file     <Xaw/ToggleP.h>
Class          toggleWidgetClass
Class Name     Toggle
Superclass      Command

   The Toggle widget is an area, often rectangular, that displays
   a graphic. The graphic may be a text string containing multiple
   lines of characters in an 8 bit or 16 bit character set (to be
   displayed with a font), or in a multi-byte encoding (for use
   with a fontset). The graphic may also be a bitmap or pixmap.

   This widget maintains a Boolean state (e.g. True/False or
   On/Off) and changes state whenever it is selected. When the
   pointer is on the Toggle widget, the Toggle widget may become
   highlighted by drawing a rectangle around its perimeter. This
   highlighting indicates that the Toggle widget is ready for
   selection. When pointer button 1 is pressed and released, the
   Toggle widget indicates that it has changed state by reversing
   its foreground and background colors, and its notify action is
   invoked, calling all functions on its callback list. If the
   pointer is moved off of the widget before the pointer button is
   released, the Toggle widget reverts to its previous foreground
   and background colors, and releasing the pointer button has no
   effect. This behavior allows the user to cancel the operation.

   Toggle widgets may also be part of a ``radio group.'' A radio
   group is a list of at least two Toggle widgets in which no more
   than one Toggle may be set at any time. A radio group is
   identified by the widget ID of any one of its members. The
   convenience routine XawToggleGetCurrent will return information
   about the Toggle widget in the radio group.

   Toggle widget state is preserved across changes in sensitivity.

Resources

   When creating a Toggle widget instance, the following resources
   are retrieved from the argument list or from the resource
   database:
   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   bitmap Bitmap Pixmap   None
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   callback Callback XtCallbackList   NULL
   colormap Colormap Colormap   Parent's Colormap
   cornerRoundPercent CornerRoundPercent Dimension   25
   cursor Cursor Cursor   None
   cursorName Cursor String   NULL
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   encoding Encoding UnsignedChar   XawTextEncoding8bit
   font Font XFontStruct   XtDefaultFont
   fontSet FontSet XFontSet   XtDefaultFontSet
   foreground Foreground Pixel   XtDefaultForeground
   height Height Dimension A graphic height + 2 * internalHeight
   highlightThickness Thickness Dimension A 2 (0 if Shaped)
   insensitiveBorder Insensitive Pixmap   GreyPixmap
   internalHeight Height Dimension   2
   internalWidth Width Dimension   4
   international International Boolean C False
   justify Justify Justify   XtJustifyCenter (center)
   label Label String   name of widget
   leftBitmap LeftBitmap Bitmap   None
   mappedWhenManaged MappedWhenManaged Boolean   True
   pointerColor Foreground Pixel   XtDefaultForeground
   pointerColorBackground Background Pixel   XtDefaultBackground
   radioData RadioData Pointer   Name of widget
   radioGroup Widget Widget   No radio group
   resize Resize Boolean   True
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   shapeStype ShapeStyle ShapeStyle   Rectangle
   state State Boolean   Off
   translations Translations TranslationTable   See below
   width Width Dimension A graphic width + 2 * internalWidth
   x Position Position   0
   y Position Position   0

   radioData
          Specifies the data that will be returned by
          XawToggleGetCurrent when this is the currently set
          widget in the radio group. This value is also used to
          identify the Toggle that will be set by a call to
          XawToggleSetCurrent. The value NULL will be returned by
          XawToggleGetCurrent if no widget in a radio group is
          currently set. Programmers must not specify NULL (or
          Zero) as radioData.

   radioGroup
          Specifies another Toggle widget that is in the radio
          group to which this Toggle widget should be added. A
          radio group is a group of at least two Toggle widgets,
          only one of which may be set at a time. If this value is
          NULL (the default) then the Toggle will not be part of
          any radio group and can change state without affecting
          any other Toggle widgets. If the widget specified in
          this resource is not already in a radio group then a new
          radio group will be created containing these two Toggle
          widgets. No Toggle widget can be in multiple radio
          groups. The behavior of a radio group of one toggle is
          undefined. A converter is registered which will convert
          widget names to widgets without caching.

   state
          Specifies whether the Toggle widget is set (True) or
          unset (False).

Toggle Actions

   The Toggle widget supports the following actions:
     * Switching the Toggle widget between the foreground and
       background colors with set and unset and toggle
     * Processing application callbacks with notify
     * Switching the internal border between highlighted and
       unhighlighted states with highlight and unhighlight

   The following are the default translation bindings used by the
   Toggle widget:
     <EnterWindow>:     highlight(Always)
     <LeaveWindow>:     unhighlight()
     <Btn1Down>,<Btn1Up>:     toggle() notify()

Toggle Actions_b

   The full list of actions supported by Toggle is:

   highlight(condition)
          Displays the internal highlight border in the color
          (foreground or background ) that contrasts with the
          interior color of the Toggle widget. The conditions
          WhenUnset and Always are understood by this action
          procedure. If no argument is passed then WhenUnset is
          assumed.

   unhighlight()
          Displays the internal highlight border in the color
          (foreground or background ) that matches the interior
          color of the Toggle widget.

   set()
          Enters the set state, in which notify is possible. This
          action causes the Toggle widget to display its interior
          in the foreground color. The label or bitmap is
          displayed in the background color.

   unset()
          Cancels the set state and displays the interior of the
          Toggle widget in the background color. The label or
          bitmap is displayed in the foreground color.

   toggle()
          Changes the current state of the Toggle widget, causing
          to be set if it was previously unset, and unset if it
          was previously set. If the widget is to be set, and is
          in a radio group then this procedure may unset another
          Toggle widget causing all routines on its callback list
          to be invoked. The callback routines for the Toggle that
          is to be unset will be called before the one that is to
          be set.

   reset()
          Cancels any set or highlight and displays the interior
          of the Toggle widget in the background color, with the
          label displayed in the foreground color.

   notify()
          When the Toggle widget is in the set state this action
          calls all functions in the callback list named by the
          callback resource. The value of the call_data argument
          in these callback functions is undefined.

   When a bitmap of depth greater that one (1) is specified the
   set(), unset(), and reset() actions have no effect, since there
   are no foreground and background colors used in a multi-plane
   pixmap.

Radio Groups

   There are typically two types of radio groups desired by
   applications. The default translations for the Toggle widget
   implement a "zero or one of many" radio group. This means that
   there may be no more than one Toggle widget active, but there
   need not be any Toggle widgets active.

   The other type of radio group is "one of many" and has the more
   strict policy that there will always be exactly one radio
   button active. Toggle widgets can be used to provide this
   interface with a slight modification to the translation table
   of each Toggle in the group.
     <EnterWindow>:     highlight(Always)
     <LeaveWindow>:     unhighlight()
     <Btn1Down>,<Btn1Up>:     set() notify()

   This translation table will not allow any Toggle to be unset
   except as a result of another Toggle becoming set. It is the
   application programmer's responsibility to choose an initial
   state for the radio group by setting the state resource of one
   of its member widgets to True.

Convenience Routines

   The following functions allow easy access to the Toggle
   widget's radio group functionality.

Changing the Toggle's Radio Group.

   To enable an application to change the Toggle's radio group,
   add the Toggle to a radio group, or remove the Toggle from a
   radio group, use XawToggleChangeRadioGroup.
   void XawToggleChangeRadioGroup( radio_group);
   Widgetw, radio_group;

   w
          Specifies the Toggle widget.

   radio_group
          Specifies any Toggle in the new radio group. If NULL
          then the Toggle will be removed from any radio group of
          which it is a member.

   If a Toggle is already set in the new radio group, and the
   Toggle to be added is also set then the previously set Toggle
   in the radio group is unset and its callback procedures are
   invoked. Finding the Currently selected Toggle in a radio group
   of Toggles

   To find the currently selected Toggle in a radio group of
   Toggle widgets use XawToggleGetCurrent.
   XtPointer XawToggleGetCurrent(
   XawToggleGetCurrent(radio_group),
     radio_group);
   XtPointer XawToggleGetCurrent(radio_group);
   Widget radio_group;

   radio_group
          Specifies any Toggle widget in the radio group.

   The value returned by this function is the radioData of the
   Toggle in this radio group that is currently set. The default
   value for radioData is the name of that Toggle widget. If no
   Toggle is set in the radio group specified then NULL is
   returned. Changing the Toggle that is set in a radio group.

   To change the Toggle that is currently set in a radio group use
   XawToggleSetCurrent.
   void XawToggleSetCurrent( radio_data),
                             radio_group,
                             radio_data);
   voidXawToggleSetCurrent(radio_group, radio_data);
   Widget radio_group;
   XtPointer radio_data;

   radio_group
          Specifies any Toggle widget in the radio group.

   radio_data
          Specifies the radioData identifying the Toggle that
          should be set in the radio group specified by the
          radio_group argument.

   XawToggleSetCurrent locates the Toggle widget to be set by
   matching radio_data against the radioData for each Toggle in
   the radio group. If none match, XawToggleSetCurrent returns
   without making any changes. If more than one Toggle matches,
   XawToggleSetCurrent will choose a Toggle to set arbitrarily. If
   this causes any Toggle widgets to change state, all routines in
   their callback lists will be invoked. The callback routines for
   a Toggle that is to be unset will be called before the one that
   is to be set. Unsetting all Toggles in a radio group.

   To unset all Toggle widgets in a radio group use
   XawToggleUnsetCurrent.
   void XawToggleUnsetCurrent( XawToggleUnsetCurrent(radio_group),

                               radio_group);
   void XawToggleUnsetCurrent(radio_group);
   Widget radio_group;

   radio_group
          Specifies any Toggle widget in the radio group.

   If this causes a Toggle widget to change state, all routines on
   its callback list will be invoked.

Chapter 4. Menus

   Table of Contents

   Using the Menus
   Sme Object

        Resources
        Subclassing the Sme Object

   SmeBSB Object

        Resources

   SmeLine Object

        Resources

   The Athena widget set provides support for single paned
   non-hierarchical popup and pulldown menus. Since menus are such
   a common user interface tool, support for them must be provided
   in even the most basic widget sets. In menuing as in other
   areas, the Athena Widget Set provides only basic functionality.

   Menus in the Athena widget set are implemented as a menu
   container (the SimpleMenu widget) and a collection of objects
   that comprise the menu entries. The SimpleMenu widget is itself
   a direct subclass of the OverrideShell widget class, so no
   other shell is necessary when creating a menu. The managed
   children of a SimpleMenu must be subclasses of the Sme (Simple
   Menu Entry) object.

   The Athena widget set provides three classes of Sme objects
   that may be used to build menus.

   Sme
          The base class of all menu entries. It may be used as a
          menu entry itself to provide blank space in a menu.
          "Sme" means "Simple Menu Entry."

   SmeBSB
          This menu entry provides a selectable entry containing a
          text string. A bitmap may also be placed in the left and
          right margins. "BSB" means "Bitmap String Bitmap."

   SmeLine
          This menu entry provides an unselectable entry
          containing a separator line.

   The SimpleMenu widget informs the window manager that it should
   ignore its window by setting the Override Redirect flag. This
   is the correct behavior for the press-drag-release style of
   menu operation. If click-move-click or "pinable" menus are
   desired it is the responsibility of the application programmer,
   using the SimpleMenu resources, to inform the window manager of
   the menu.

   To allow easy creation of pulldown menus, a MenuButton widget
   is also provided as part of the Athena widget set.

Using the Menus

   The default configuration for the menus is press-drag-release.
   The menus will typically be activated by clicking a pointer
   button while the pointer is over a MenuButton, causing the menu
   to appear in a fixed location relative to that button; this is
   a pulldown menu. Menus may also be activated when a specific
   pointer and/or key sequence is used anywhere in the
   application; this is a popup menu (e.g. clicking Ctrl-<pointer
   button 1> in the common application xterm). In this case the
   menu should be positioned under the cursor. Typically menus
   will be placed so the pointer cursor is on the first menu
   entry, or the last entry selected by the user.

   The menu remains on the screen as long as the pointer button is
   held down. Moving the pointer will highlight different menu
   items. If the pointer leaves the menu, or moves over an entry
   that cannot be selected then no menu entry will highlighted.
   When the desired menu entry has been highlighted, releasing the
   pointer button removes the menu, and causes any mechanism
   associated with this entry to be invoked.

Sme Object



Application Header file <X11/Xaw/Sme.h>

Class Header file       <X11/Xaw/SmeP.h>

Class           smeObjectClass

Class Name      Sme

Superclass      RectObj

   The Sme object is the base class for all menu entries. While
   this object is mainly intended to be subclassed, it may be used
   in a menu to add blank space between menu entries.

Resources

   The resources associated with the SmeLine object are defined in
   this section, and affect only the single menu entry specified
   by this object. There are no new resources added for this
   class, as it picks up all its resources from the RectObj class.
        Name              Class            Type      Notes Default Value
  ancestorSensitive AncestorSensitive    Boolean               True
      callback          Callback      XtCallbackList           NULL
   destroyCallback      Callback      XtCallbackList           NULL
       height            Height         Dimension                0
    international     International      Boolean       C       False
      sensitive         Sensitive        Boolean               True
        width             Width         Dimension                1

   Keep in mind that the SimpleMenu widget will force all menu
   items to be the width of the widest entry.

Subclassing the Sme Object

   To Create a new Sme object class you will need to define three
   class methods. These methods allow the SimpleMenu to highlight
   and unhighlight the menu entry as the pointer cursor moves over
   it, as well as notify the entry when the user has selected it.
   All of these methods may be inherited from the Sme object,
   although the default semantics are not very interesting.

   Highlight(\|)
          Called to put the menu entry into the highlighted state.

   Unhighlight(\|)
          Called to return the widget to its normal
          (unhighlighted) state.

   Notify(\|)
          Called when the user selects this menu entry.

   Other then these methods, creating a new object is straight
   forward. Here is some information that may help you avoid some
   common mistakes.
    1. Objects can be zero pixels high.
    2. Objects draw on their parent's window, therefore the
       Drawing dimensions are different from those of widgets. For
       instance, y locations vary from y to y + height, not 0 to
       height.
    3. XtSetValues calls may come from the application while the
       Sme is highlighted, and if the SetValues method returns
       True, will result in an expose event. The SimpleMenu may
       later call the menu entry's unhighlight procedure. However,
       due to the asynchronous nature of X, the expose event
       generated by XtSetValues will come after this unhighlight.
    4. Remember that your subclass of the Sme does not own the
       window. Share the space with other menu entries, and
       refrain from drawing outside the subclass's own section of
       the menu.

SmeBSB Object




Application Header file <X11/Xaw/SmeBSB.h>

Class Header file       <X11/Xaw/SmeBSBP.h>

Class           smeBSBObjectClass

Class Name      SmeBSB

Superclass      Sme


   The SmeBSB object is used to create a menu entry that contains
   a string, and optional bitmaps in its left and right margins.
   Since each menu entry is an independent object, the application
   is able to change the font, color, height, and other attributes
   of the menu entries, on an entry by entry basis. The format of
   the string may either be the encoding of the 8 bit font
   utilized, or in a multi-byte encoding for use with a fontSet.

Resources

   The resources associated with the SmeBSB object are defined in
   this section, and affect only the single menu entry specified
   by this object.
   Name Class Type Notes Default Value
   ancestorSensitive AncestorSensitive Boolean D True
   callback Callback Callback   NULL
   destroyCallback Callback XtCallbackList   NULL
   font Font FontStruct   XtDefaultFont
   fontSet FontSet XFontSet   XtDefaultFontSet
   foreground Foreground Pixel   XtDefaultForeground
   height Height Dimension A Font height + vertSpace
   international International Boolean C False
   justify Justify Justify   XtjustifyLeft
   label Label String   NULL
   leftBitmap LeftBitmap Pixmap   XtUnspecifiedPixmap
   leftMargin leftMargin Dimension   4
   rightBitmap RightBitmap Pixmap   XtUnspecifiedPixmap
   rightMargin rightMargin Dimension   4
   sensitive Sensitive Boolean   True
   vertSpace VertSpace int   25
   width Width Dimension A TextWidth + margins

   callback
          All callback functions on this list are called when the
          SimpleMenu notifies this entry that the user has
          selected it.

   font
          The text font to use when displaying the label, when the
          international resource is false.

   fontSet
          The text font set to use when displaying the label, when
          the international resource is true.

   foreground
          A pixel value which indexes the SimpleMenu's colormap to
          derive the foreground color of the menu entry's window.
          This color is also used to render all 1's in the left
          and right bitmaps. Keep in mind that the SimpleMenu
          widget will force the width of all menu entries to be
          the width of the longest entry.

   justify
          How the label is to be rendered between the left and
          right margins when the space is wider than the actual
          text. This resource may be specified with the values
          XtJustifyLeft, XtJustifyCenter, or XtJustifyRight. When
          specifying the justification from a resource file the
          values left, center, or right may be used.

   label
          This is a the string that will be displayed in the menu
          entry. The exact location of this string within the
          bounds of the menu entry is controlled by the
          leftMargin, rightMargin, vertSpace, and justify
          resources.

   leftBitmap

   rightBitmap
          This is a name of a bitmap to display in the left or
          right margin of the menu entry. All 1's in the bitmap
          will be rendered in the foreground color, and all 0's
          will be drawn in the background color of the SimpleMenu
          widget. It is the programmers' responsibility to make
          sure that the menu entry is tall enough, and the
          appropriate margin wide enough to accept the bitmap. If
          care is not taken the bitmap may extend into another
          menu entry, or into this entry's label.

   leftMargin

   rightMargin
          This is the amount of space (in pixels) that will be
          left between the edge of the menu entry and the label
          string.

   vertSpace
          This is the amount of vertical padding, expressed as a
          percentage of the height of the font, that is to be
          placed around the label of a menu entry.. The label and
          bitmaps are always centered vertically within the menu.
          The default value for this resource (25) causes the
          default height to be 125% of the height of the font.

SmeLine Object



Application Header file <X11/Xaw/SmeLine.h>

Class Header file       <X11/Xaw/SmeLineP.h>

Class           smeLineObjectClass

Class Name      SmeLine

Superclass      Sme

   The SmeLine object is used to add a horizontal line or menu
   separator to a menu. Since each SmeLine is an independent
   object, the application is able to change the color, height,
   and other attributes of the SmeLine objects on an entry by
   entry basis. This object is not selectable, and will not
   highlight when the pointer cursor is over it.

Resources

   The resources associated with the SmeLine object are defined in
   this section, and affect only the single menu entry specified
   by this object.
       Name           Class          Type      Notes    Default Value
  destroyCallback   Callback    XtCallbackList              NULL
    foreground     Foreground       Pixel            XtDefaultForeground
      height         Height       Dimension               lineWidth
   international  International    Boolean       C          False
     lineWidth      LineWidth     Dimension                   1
      stipple        Stipple        Pixmap           XtUnspecifiedPixmap
       width          Width       Dimension                   1

   foreground
          A pixel value which indexes the SimpleMenu's colormap to
          derive the foreground color used to draw the separator
          line. Keep in mind that the SimpleMenu widget will force
          all menu items to be the width of the widest entry.
          Thus, setting the width is generally not very important.

   lineWidth
          The width of the horizontal line that is to be
          displayed.

   stipple
          If a bitmap is specified for this resource, the line
          will be stippled through it. This allows the menu
          separator to be rendered as something more exciting than
          just a line. For instance, if you define a stipple that
          is a chain link, then your menu separators will look
          like chains.

Chapter 5. Text Widgets

   Table of Contents

   Text Widget for Users

        Default Key Bindings
        Search and Replace
        File Insertion
        Text Selections for Users

   Text Widget Actions

        Cursor Movement Actions\fP
        Delete Actions
        Selection Actions
        The New Line Actions
        Kill and Actions
        Miscellaneous Actions
        Text Selections for Application Programmers

   Default Translation Bindings
   Text Functions

        Selecting Text
        Unhighlighting Text
        Getting Current Text Selection
        Replacing Text
        Searching for Text
        Redisplaying Text
        Resources Convenience Routines

   Customizing the Text Widget
   Text Widget

        Resources

   TextSink Object

        Resources
        Subclassing the TextSink

   TextSrc Object

        Resources
        Subclassing the TextSrc

   Ascii Sink Object and Multi Sink Object

        Resources

   Ascii Source Object and Multi Source Object

        Resources
        Convenience Routines

   Ascii Text Widget

        Resources

   The Text widget provides a window that will allow an
   application to display and edit one or more lines of text.
   Options are provided to allow the user to add Scrollbars to its
   window, search for a specific string, and modify the text in
   the buffer.

   The Text widget is made up of a number of pieces; it was
   modularized to ease customization. The AsciiText widget class
   (actually not limited to ASCII but so named for compatibility)
   is be general enough to most needs. If more flexibility,
   special features, or extra functionality is needed, they can be
   added by implementing a new TextSource or TextSink, or by
   subclassing the Text Widget (See Section 5.8 for customization
   details.)

   The words insertion point are used in this chapter to refer to
   the text caret. This is the symbol that is displayed between
   two characters in the file. The insertion point marks the
   location where any new characters will be added to the file. To
   avoid confusion the pointer cursor will always be referred to
   as the pointer.

   The text widget supports three edit modes, controlling the
   types of modifications a user is allowed to make:

     * Append-only
     * Editable
     * Read-only

   Read-only mode does not allow the user or the programmer to
   modify the text in the widget. While the entire string may be
   reset in read-only mode with XtSetValues, it cannot be modified
   via with XawTextReplace. Append-only and editable modes allow
   the text at the insertion point to be modified. The only
   difference is that text may only be added to or removed from
   the end of a buffer in append-only mode.

Text Widget for Users

   The Text widget provides many of the common keyboard editing
   commands. These commands allow users to move around and edit
   the buffer. If an illegal operation is attempted, (such as
   deleting characters in a read-only text widget), the X server
   will beep.

Default Key Bindings

   The default key bindings are patterned after those in the EMACS
   text editor:


Ctrl-a  Beginning Of Line       Meta-b  Backward Word
Ctrl-b  Backward Character      Meta-f  Forward Word
Ctrl-d  Delete Next Character   Meta-i  Insert File
Ctrl-e  End Of Line     Meta-k  Kill To End Of Paragraph
Ctrl-f  Forward Character       Meta-q  Form Paragraph
Ctrl-g  Multiply Reset  Meta-v  Previous Page
Ctrl-h  Delete Previous Character       Meta-y  Insert Current Selection
Ctrl-j  Newline And Indent      Meta-z  Scroll One Line Down
Ctrl-k  Kill To End Of Line     Meta-d  Delete Next Word
Ctrl-l  Redraw Display  Meta-D  Kill Word
Ctrl-m  Newline Meta-h  Delete Previous Word
Ctrl-n  Next Line       Meta-H  Backward Kill Word
Ctrl-o  Newline And Backup      Meta-<  Beginning Of File
Ctrl-p  Previous Line   Meta->  End Of File
Ctrl-r  Search/Replace Backward Meta-]  Forward Paragraph
Ctrl-s  Search/Replace Forward  Meta-[  Backward Paragraph
Ctrl-t  Transpose Characters
Ctrl-u  Multiply by 4   Meta-Delete     Delete Previous Word
Ctrl-v  Next Page       Meta-Shift Delete       Kill Previous Word
Ctrl-w  Kill Selection  Meta-Backspace  Delete Previous Word
Ctrl-y  Unkill  Meta-Shift Backspace    Kill Previous Word
Ctrl-z  Scroll One Line Up
Ctrl-\\ Reconnect to input method
Kanji   Reconnect to input method

   In addition, the pointer may be used to cut and paste text:



        Button 1 Down   Start Selection
        Button 1 Motion Adjust Selection
        Button 1 Up     End Selection (cut)

        Button 2 Down   Insert Current Selection (paste)

        Button 3 Down   Extend Current Selection
        Button 3 Motion Adjust Selection
        Button 3 Up     End Selection (cut)


   Since all of these key and pointer bindings are set through the
   translations and resource manager, the user and the application
   programmer can modify them by changing the Text widget's
   translations resource.

Search and Replace

   The Text widget provides a search popup that can be used to
   search for a string within the current Text widget. The popup
   can be activated by typing either Control-r or Control-s. If
   Control-s is used the search will be forward in the file from
   the current location of the insertion point; if Control-r is
   used the search will be backward. The activated popup is placed
   under the pointer. It has a number of buttons that allow both
   text searches and text replacements to be performed.

   At the top of the search popup are two toggle buttons labeled
   backward and forward. One of these buttons will always be
   highlighted; this is the direction in which the search will be
   performed. The user can change the direction at any time by
   clicking on the appropriate button.

   Directly under the buttons there are two text areas, one
   labeled Search for: and the other labeled Replace with:. If
   this is a read-only Text widget the Replace with: field will be
   insensitive and no replacements will be allowed. After each of
   these labels will be a text field. This field will allow the
   user to enter a string to search for and the string to replace
   it with. Only one of these text fields will have a window
   border around it; this is the active text field. Any key
   presses that occur when the focus in in the search popup will
   be directed to the active text field. There are also a few
   special key sequences:


Carriage Return:        Execute the action, and pop down the search widg
et.
Tab:    Execute the action, then move to the next field.
Shift Carriage Return:  Execute the action, then move to the next field.
Control-q Tab:  Enter a Tab into a text field.
Control-c:      Pop down the search popup.

   Using these special key sequences should allow simple searches
   without ever removing one's hands from the keyboard.

   Near the bottom of the search popup is a row of buttons. These
   buttons allow the same actions to to be performed as the key
   sequences, but the buttons will leave the popup active. This
   can be quite useful if many searches are being performed, as
   the popup will be left on the display. Since the search popup
   is a transient window, it may be picked up with the window
   manager and pulled off to the side for use at a later time.

   Search
          Search for the specified string.

   Replace
          Replace the currently highlighted string with the string
          in the Replace with text field, and move onto the next
          occurrence of the Search for text field. The
          functionality is commonly referred to as query-replace.

   ReplaceAll
          Replace all occurrences of the search string with the
          replace string from the current insertion point position
          to the end (or beginning) of the file. There is no key
          sequence to perform this action.

   ReplaceAll
          Remove the search popup from the screen.

   Finally, when international resource is true, there may be a
   pre-edit buffer below the button row, for composing input. Its
   presence is determined by the X locale in use and the
   VendorShell's preeditType resource.

   The widget hierarchy for the search popup is show below, all
   widgets are listed by class and instance name.
Text  <name of Text widget>
        TransientShell  search
                Form  form
                        Label label1
                        Label  label2
                        Toggle  backwards
                        Toggle  forwards
                        Label  searchLabel
                        Text  searchText
                        Label  replaceLabel
                        Text  replaceText
                        Command  search
                        Command  replaceOne
                        Command  replaceAll
                        Command  cancel

File Insertion

   To insert a file into a text widget, type the key sequence
   Meta-i, which will activate the file insert popup. This popup
   will appear under the pointer, and any text typed while the
   focus is in this popup will be redirected to the text field
   used for the filename. When the desired filename has been
   entered, click on Insert File, or type Carriage Return. The
   named file will then be inserted in the text widget beginning
   at the insertion point position. If an error occurs when
   opening the file, an error message will be printed, prompting
   the user to enter the filename again. The file insert may be
   aborted by clicking on Cancel. If Meta-i is typed at a text
   widget that is read-only, it will beep, as no file insertion is
   allowed.

   The widget hierarchy for the file insert popup is show below;
   all widgets are listed by class and instance name.
Text  <name of Text widget>
        TransientShell  insertFile
                Form  form
                        Label  label
                        Text  text
                        Command  insert
                        Command  cancel

Text Selections for Users

   The text widgets have a text selection mechanism that allows
   the user to copy pieces of the text into the PRIMARY selection,
   and paste into the text widget some text that another
   application (or text widget) has put in the PRIMARY selection.

   One method of selecting text is to press pointer button 1 on
   the beginning of the text to be selected, drag the pointer
   until all of the desired text is highlighted, and then release
   the button to activate the selection. Another method is to
   click pointer button 1 at one end of the text to be selected,
   then click pointer button 3 at the other end.

   To modify a currently active selection, press pointer button 3
   near either the end of the selection that you want to adjust.
   This end of the selection may be moved while holding down
   pointer button 3. When the proper area has been highlighted
   release the pointer button to activate the selection.

   The selected text may now be pasted into another application,
   and will remain active until some other client makes a
   selection. To paste text that some other application has put
   into the PRIMARY selection use pointer button 2. First place
   the insertion point where you would like the text to be
   inserted, then click and release pointer button 2.

   Rapidly clicking pointer button 1 the following number of times
   will adjust the selection as described.

   Two
          Select the word under the pointer. A word boundary is
          defined by the Text widget to be a Space, Tab, or
          Carriage Return.

   Three
          Select the line under the pointer.

   Four
          Select the paragraph under the pointer. A paragraph
          boundary is defined by the text widget as two Carriage
          Returns in a row with only Spaces or Tabs between them.

   Five
          Select the entire text buffer.

   To unset the text selection, click pointer button 1 without
   moving it.

Text Widget Actions

   All editing functions are performed by translation manager
   actions that may be specified through the translations resource
   in the Text widget.



Insert Point Movement     Delete
     forward-character         delete-next-character
     backward-character        delete-previous-character
     forward-word              delete-next-word
     backward-word             delete-previous-word
     forward-paragraph         delete-selection
     backward-paragraph
     beginning-of-line
     end-of-line          Selection
     next-line                 select-word
     previous-line             select-all
     next-page                 select-start
     previous-page             select-adjust
     beginning-of-file         select-end
     end-of-file               extend-start
     scroll-one-line-up        extend-adjust
     scroll-one-line-down      extend-end
                               insert-selection


Miscellaneous             New Line
     redraw-display            newline-and-indent
     insert-file               newline-and-backup
     insert-char               newline
     insert-string
     display-caret
     focus-in             Kill
     focus-in                  kill-word
     search                    backward-kill-word
     multiply                  kill-selection
     form-paragraph            kill-to-end-of-line
     transpose-characters      kill-paragraph
     no-op                     kill-to-end-of-paragraph
     XawWMProtocols
     reconnect-im

   Most of the actions take no arguments, and unless otherwise
   noted you may assume this to be the case.

Cursor Movement Actions\fP

   forward-character()

   backward-character()
          These actions move the insert point forward or backward
          one character in the buffer. If the insert point is at
          the end or beginning of a line this action will move the
          insert point to the next (or previous) line.

   forward-word()

   backward-word()
          These actions move the insert point to the next or
          previous word boundary. A word boundary is defined as a
          Space, Tab or Carriage Return.

   forward-paragraph()

   backward-paragraph()
          These actions move the insert point to the next or
          previous paragraph boundary. A paragraph boundary is
          defined as two Carriage Returns in a row with only
          Spaces or Tabs between them.

   beginning-of-line()

   end-of-line()
          These actions move to the beginning or end of the
          current line. If the insert point is already at the end
          or beginning of the line then no action is taken.

   next-line()

   previous-line()
          These actions move the insert point up or down one line.
          If the insert point is currently N characters from the
          beginning of the line then it will be N characters from
          the beginning of the next or previous line. If N is past
          the end of the line, the insert point is placed at the
          end of the line.

   next-page()

   previous-page()
          These actions move the insert point up or down one page
          in the file. One page is defined as the current height
          of the text widget. The insert point is always placed at
          the first character of the top line by this action.

   beginning-of-file()

   end-of-file()
          These actions place the insert point at the beginning or
          end of the current text buffer. The text widget is then
          scrolled the minimum amount necessary to make the new
          insert point location visible.

   scroll-one-line-up()

   scroll-one-line-down()
          These actions scroll the current text field up or down
          by one line. They do not move the insert point. Other
          than the scrollbars this is the only way that the insert
          point may be moved off of the visible text area. The
          widget will be scrolled so that the insert point is back
          on the screen as soon as some other action is executed.

Delete Actions

   delete-next-character()

   delete-previous-character()
          These actions remove the character immediately before or
          after the insert point. If a Carriage Return is removed
          then the next line is appended to the end of the current
          line.

   delete-next-word()

   delete-previous-word()
          These actions remove all characters between the insert
          point location and the next word boundary. A word
          boundary is defined as a Space, Tab or Carriage Return.

   delete-selection()
          This action removes all characters in the current
          selection. The selection can be set with the selection
          actions.

Selection Actions

   select-word()
          This action selects the word in which the insert point
          is currently located. If the insert point is between
          words then it will select the previous word.

   select-all()
          This action selects the entire text buffer.

   select-start()
          This action sets the insert point to the current pointer
          location (if triggered by a button event) or text cursor
          location (if triggered by a key event). It will then
          begin a selection at this location. If many of these
          selection actions occur quickly in succession then the
          selection count mechanism will be invoked (see the
          section titled \fBText Selections for Application
          Programmers\fP for details).

   select-adjust()
          This action allows a selection started with the
          select-start action to be modified, as described above.

   select-end(name[,name,...])
          This action ends a text selection that began with the
          select-start action, and asserts ownership of the
          selection or selections specified. A name can be a
          selection (e.g., PRIMARY) or a cut buffer (e.g.,
          CUT_BUFFER0). Note that case is important. If no names
          are specified, PRIMARY is asserted.

   extend-start()
          This action finds the nearest end of the current
          selection, and moves it to the current pointer location
          (if triggered by a button event) or text cursor location
          (if triggered by a key event).

   extend-adjust()
          This action allows a selection started with an
          extend-start action to be modified.

   extend-end(name[,name,...])
          This action ends a text selection that began with the
          extend-start action, and asserts ownership of the
          selection or selections specified. A name can be a
          selection (e.g. PRIMARY) or a cut buffer (e.g
          CUT_BUFFER0). Note that case is important. If no names
          are given, PRIMARY is asserted.

   insert-selection(name[,name,...])
          This action retrieves the value of the first (left-most)
          named selection that exists or the cut buffer that is
          not empty and inserts it into the Text widget at the
          current insert point location. A name can be a selection
          (e.g. PRIMARY) or a cut buffer (e.g CUT_BUFFER0). Note
          that case is important.

The New Line Actions

   newline-and-indent()
          This action inserts a newline into the text and adds
          spaces to that line to indent it to match the previous
          line.

   newline-and-backup()
          This action inserts a newline into the text after the
          insert point.

   newline()
          This action inserts a newline into the text before the
          insert point.

Kill and Actions

   kill-word()

   backward-kill-word()
          These actions act exactly like the delete-next-word and
          delete-previous-word actions, but they stuff the word
          that was killed into the kill buffer (CUT_BUFFER_1).

   kill-selection()
          This action deletes the current selection and stuffs the
          deleted text into the kill buffer (CUT_BUFFER_1).

   kill-to-end-of-line()
          This action deletes the entire line to the right of the
          insert point position, and stuffs the deleted text into
          the kill buffer (CUT_BUFFER_1).

   kill-paragraph()
          This action deletes the current paragraph, if between
          paragraphs it deletes the paragraph above the insert
          point, and stuffs the deleted text into the kill buffer
          (CUT_BUFFER_1).

   kill-to-end-of-paragraph()
          This action deletes everything between the current
          insert point location and the next paragraph boundary,
          and stuffs the deleted text into the kill buffer
          (CUT_BUFFER_1).

Miscellaneous Actions

   redraw-display()
          This action recomputes the location of all the text
          lines on the display, scrolls the text to vertically
          center the line containing the insert point on the
          screen, clears the entire screen, and redisplays it.

   insert-file([filename])
          This action activates the insert file popup. The
          filename option specifies the default filename to put in
          the filename buffer of the popup. If no filename is
          specified the buffer is empty at startup.

   insert-char()
          This action may only be attached to a key event. When
          the international resource is false, this action calls
          XLookupString to translate the event into a (rebindable)
          Latin-1 character (sequence) and inserts it into the
          text at the insert point. When the international
          resource is true, characters are passed to the input
          method via XwcLookupString, and any committed string
          returned is inserted into the text at the insert point.

   insert-string(string[,string,...])
          This action inserts each string into the text at the
          insert point location. Any string beginning with the
          characters "0x" followed by an even number of
          hexadecimal digits is interpreted as a hexadecimal
          constant and the corresponding string is inserted
          instead. This hexadecimal string may represent up to 50
          8-bit characters. When theinternational resource is
          true, a hexadecimal string is intrepeted as being in a
          multi-byte encoding, and a hexadecimal or regular string
          will result in an error message if it is not legal in
          the current locale.

   display-caret(state,when)
          This action allows the insert point to be turned on and
          off. The state argument specifies the desired state of
          the insert point. This value may be any of the string
          values accepted for Boolean resources (e.g. on, True,
          off, False, etc.). If no arguments are specified, the
          default value is True. The when argument specifies, for
          EnterNotify or LeaveNotify events whether or not the
          focus field in the event is to be examined. If the
          second argument is not specified, or specified as
          something other than always then if the action is bound
          to an EnterNotify or LeaveNotify event, the action will
          be taken only if the focus field is True. An augmented
          binding that might be useful is:



     *Text.Translations: #override \\
          <FocusIn>:     display-caret(on) \\n\\
          <FocusOut>:     display-caret(off)

   focus-in()

   focus-out()
          These actions do not currently do anything.

   search(direction,[string])
          This action activates the search popup. The direction
          must be specified as either forward or backward. The
          string is optional and is used as an initial value for
          the Search for: string. For further explanation of the
          search widget see the section on Text Searches.

   multiply(value)
          The multiply action allows the user to multiply the
          effects of many of the text actions. Thus the following
          action sequence multiply(10) delete-next-word() will
          delete 10 words. It does not matter whether these
          actions take place in one event or many events. Using
          the default translations the key sequence \fIControl-u,
          Control-d\fP will delete 4 characters. Multiply actions
          can be chained, thus \fImultiply(5) multiply(5)\fP is
          the same as multiply(25). If the string reset is passed
          to the multiply action the effects of all previous
          multiplies are removed and a beep is sent to the
          display.

   form-paragraph()
          This action removes all the Carriage Returns from the
          current paragraph and reinserts them so that each line
          is as long as possible, while still fitting on the
          current screen. Lines are broken at word boundaries if
          at all possible. This action currently works only on
          Text widgets that use ASCII text.

   transpose-characters()
          This action will swap the position of the character to
          the left of the insert point with the character to the
          right of the insert point. The insert point will then be
          advanced one character.

   no-op([action])
          The no-op action makes no change to the text widget, and
          is mainly used to override translations. This action
          takes one optional argument. If this argument is
          RingBell then a beep is sent to the display.

   XawWMProtocols([wm_protocol_name])
          This action is written specifically for the file
          insertion and the search and replace dialog boxes. This
          action is attached to those shells by the Text widget,
          in order to handle ClientMessage events with the
          WM_PROTOCOLS atom in the detail field. This action
          supports WM_DELETE_WINDOW on the Text widget popups, and
          may support other window manager protocols if necessary
          in the future. The popup will be dismissed if the window
          manager sends a WM_DELETE_WINDOW request and there are
          no parameters in the action call, which is the default.
          The popup will also be dismissed if the parameters
          include the string ``wm_delete_window,'' and the event
          is a ClientMessage event requesting dismissal or is not
          a ClientMessage event. This action is not sensitive to
          the case of the strings passed as parameters.

   reconnect-im()
          When the international resource is true, input is
          usually passed to an input method, a separate process,
          for composing. Sometimes the connection to this process
          gets severed; this action will attempt to reconnect it.
          Causes for severage include network trouble, and the
          user explicitly killing one input method and starting a
          new one. This action may also establish first connection
          when the application is started before the input method.

Text Selections for Application Programmers

   The default behavior of the text selection array is described
   in the section called Text Selections for Users. To modify the
   selections a programmer must construct a XawTextSelectType
   array (called the selection array), containing the selections
   desired, and pass this as the new value for the selectionTypes
   resource. The selection array may also be modified using the
   XawTextSetSelectionArray function. All selection arrays must
   end with the value XawselectNull. The selectionTypes resource
   has no converter registered and cannot be modified through the
   resource manager.

   The array contains a list of entries that will be called when
   the user attempts to select text in rapid succession with the
   select-start action (usually by clicking a pointer button). The
   first entry in the selection array will be used when the
   select-start action is initially called. The next entry will be
   used when select-start is called again, and so on. If a timeout
   value (1/10 of a second) is exceeded, the the next select-start
   action will begin at the top of the selection array. When
   XawselectNull is reached the array is recycled beginning with
   the first element.
   XawselectAll Selects the contents of the entire buffer.
   XawselectChar Selects text characters as the pointer moves over
   them.
   XawselectLine Selects the entire line.
   XawselectNull Indicates the end of the selection array.
   XawselectParagraph Selects the entire paragraph.
   XawselectPosition Selects the current pointer position.
   XawselectWord Selects whole words as the pointer moves onto
   them.

   The default selectType array is:

{XawselectPosition, XawselectWord, XawselectLine, XawselectParagraph, Xa
wselectAll, XawselectNull}

   The selection array is not copied by the text widgets. The
   application must allocate space for the array and cannot
   deallocate or change it until the text widget is destroyed or
   until a new selection array is set.

Default Translation Bindings

   The following translations are defaults built into every Text
   widget. They can be overridden, or replaced by specifying a new
   value for the Text widget's translations resource.



     Ctrl<Key>A:     beginning-of-line() \\n\\
     Ctrl<Key>B:     backward-character() \\n\\
     Ctrl<Key>D:     delete-next-character() \\n\\
     Ctrl<Key>E:     end-of-line() \\n\\
     Ctrl<Key>F:     forward-character() \\n\\
     Ctrl<Key>G:     multiply(Reset) \\n\\
     Ctrl<Key>H:     delete-previous-character() \\n\\
     Ctrl<Key>J:     newline-and-indent() \\n\\
     Ctrl<Key>K:     kill-to-end-of-line() \\n\\
     Ctrl<Key>L:     redraw-display() \\n\\
     Ctrl<Key>M:     newline() \\n\\
     Ctrl<Key>N:     next-line() \\n\\
     Ctrl<Key>O:     newline-and-backup() \\n\\
     Ctrl<Key>P:     previous-line() \\n\\
     Ctrl<Key>R:     search(backward) \\n\\
     Ctrl<Key>S:     search(forward) \\n\\
     Ctrl<Key>T:     transpose-characters() \\n\\
     Ctrl<Key>U:     multiply(4) \\n\\
     Ctrl<Key>V:     next-page() \\n\\
     Ctrl<Key>W:     kill-selection() \\n\\
     Ctrl<Key>Y:     insert-selection(CUT_BUFFER1) \\n\\
     Ctrl<Key>Z:     scroll-one-line-up() \\n\\
     Ctrl<Key>\\:     reconnect-im() \\n\\
     Meta<Key>B:     backward-word() \\n\\
     Meta<Key>F:     forward-word() \\n\\
     Meta<Key>I:     insert-file() \\n\\
     Meta<Key>K:     kill-to-end-of-paragraph() \\n\\
     Meta<Key>Q:     form-paragraph() \\n\\
     Meta<Key>V:     previous-page() \\n\\
     Meta<Key>Y:     insert-selection(PRIMARY, CUT_BUFFER0) \\n\\
     Meta<Key>Z:     scroll-one-line-down() \\n\\
     :Meta<Key>d:     delete-next-word() \\n\\
     :Meta<Key>D:     kill-word() \\n\\
     :Meta<Key>h:     delete-previous-word() \\n\\
     :Meta<Key>H:     backward-kill-word() \\n\\
     :Meta<Key>\\<:     beginning-of-file() \\n\\
     :Meta<Key>\\>:     end-of-file() \\n\\
     :Meta<Key>]:     forward-paragraph() \\n\\
     :Meta<Key>[:     backward-paragraph() \\n\\
     ~Shift Meta<Key>Delete:          delete-previous-word() \\n\\
     \ Shift Meta<Key>Delete:          backward-kill-word() \\n\\
     ~Shift Meta<Key>Backspace:     delete-previous-word() \\n\\
     \ Shift Meta<Key>Backspace:     backward-kill-word() \\n\\
     <Key>Right:     forward-character() \\n\\
     <Key>Left:     backward-character() \\n\\
     <Key>Down:     next-line() \\n\\
     <Key>Up:     previous-line() \\n\\
     <Key>Delete:     delete-previous-character() \\n\\
     <Key>BackSpace:     delete-previous-character() \\n\\
     <Key>Linefeed:     newline-and-indent() \\n\\
     <Key>Return:     newline() \\n\\
     <Key>:          insert-char() \\n\\
     <Key>Kanji:     reconnect-im() \\n\\
     <FocusIn>:     focus-in() \\n\\
     <FocusOut>:     focus-out() \\n\\
     <Btn1Down>:     select-start() \\n\\
     <Btn1Motion>:     extend-adjust() \\n\\
     <Btn1Up>:     extend-end(PRIMARY, CUT_BUFFER0) \\n\\
     <Btn2Down>:     insert-selection(PRIMARY, CUT_BUFFER0) \\n\\
     <Btn3Down>:     extend-start() \\n\\
     <Btn3Motion>:     extend-adjust() \\n\\
     <Btn3Up>:     extend-end(PRIMARY, CUT_BUFFER0) \\n

Text Functions

   The following functions are provided as convenience routines
   for use with the Text widget. Although many of these actions
   can be performed by modifying resources, these interfaces are
   frequently more efficient.

   These data structures are defined in the Text widget's public
   header file, <X11/Xaw/Text.h>.

   typedef long XawTextPosition;

   Character positions in the Text widget begin at 0 and end at n,
   where n is the number of characters in the Text source widget.



typedef struct {
        int firstPos;
        int length;
        char *ptr;
        unsigned long format;
} XawTextBlock, *XawTextBlockPtr;

   firstPos
          The first position, or index, to use within the ptr
          field. The value is commonly zero.

   length
          The number of characters to be used from the ptr field.
          The number of characters used is commonly the number of
          characters in ptr, and must not be greater than the
          length of the string in ptr.

   ptr
          Contains the string to be referenced by the Text widget.

   format
          This flag indicates whether the data pointed to by ptr
          is char or wchar_t. When the associated widget has
          international set to false this field must be
          XawFmt8Bit. When the associated widget has international
          set to true this field must be either XawFmt8Bit or
          XawFmtWide.

Note

   Note: Previous versions of Xaw used FMT8BIT , which has been
   retained for backwards compatibility. FMT8BIT is deprecated and
   will eventually be removed from the implementation.

Selecting Text

   To select a piece of text, use XawTextSetSelection :
   void XawTextSetSelection( w,
                             right);
   Widget w;
   XawTextPositionleft, right;

   w
          Specifies the Text widget.

   left
          Specifies the character position at which the selection
          begins.

   right
          Specifies the character position at which the selection
          ends.

   See section 5.4 for a description of XawTextPosition. If
   redisplay is enabled, this function highlights the text and
   makes it the PRIMARY selection. This function does not have any
   effect on CUT_BUFFER0.

Unhighlighting Text

   To unhighlight previously highlighted text in a widget, use
   XawTextUnsetSelection:
   void XawTextUnsetSelection( w);
   Widget w;

   w
          Specifies the Text widget.

Getting Current Text Selection

   To retrieve the text that has been selected by this text widget
   use XawTextGetSelectionPos:
   void XawTextGetSelectionPos( w,
                                *end_return);
   Widget w;
   XawTextPosition*begin_return, *end_return;

   w
          Specifies the Text widget.

   begin_return
          Returns the beginning of the text selection.

   end_return
          Returns the end of the text selection.

   See section 5.4 for a description of XawTextPosition. If the
   returned values are equal, no text is currently selected.

Replacing Text

   To modify the text in an editable Text widget use
   XawTextReplace:
   int XawTextReplace( w,
                       end,
                       *text);
   Widget w;
   XawTextPositionstart, end;
   XawTextBlock *text;

   w
          Specifies the Text widget.

   start
          Specifies the starting character position of the text
          replacement.

   end
          Specifies the ending character position of the text
          replacement.

   text
          Specifies the text to be inserted into the file.

   This function will not be able to replace text in read-only
   text widgets. It will also only be able to append text to an
   append-only text widget.

   See section 5.4 for a description of XawTextPosition and
   XawTextBlock.

   This function may return the following values:

   XawEditDone
          The text replacement was successful.

   XawPositionError
          The edit mode is XawtextAppend and start is not the
          position of the last character of the source.

   XawEditError
          Either the Source was read-only or the range to be
          deleted is larger than the length of the Source.

   The XawTextReplace arguments start and end represent the text
   source character positions for the existing text that is to be
   replaced by the text in the text block. The characters from
   start up to but not including end are deleted, and the
   characters specified on the text block are inserted in their
   place. If start and end are equal, no text is deleted and the
   new text is inserted after start.

Searching for Text

   To search for a string in the Text widget, use XawTextSearch:
   XawTextPosition XawTextSearch( w,
                                  dir,
                                  text);
   Widget w;
   XawTextScanDirection dir;
   XawTextBlock* text;

   w
          Specifies the Text widget.

   dir
          Specifies the direction to search in. Legal values are
          XawsdLeft and XawsdRight.

   text
          Specifies a text block structure that contains the text
          to search for.

   See section 5.4 for a description of XawTextPosition and
   XawTextBlock. The XawTextSearch function will begin at the
   insertion point and search in the direction specified for a
   string that matches the one passed in text. If the string is
   found the location of the first character in the string is
   returned. If the string could not be found then the value
   XawTextSearchError is returned.

Redisplaying Text

   To redisplay a range of characters, use XawTextInvalidate:
   void XawTextInvalidate( w,
                           to);
   Widget w;
   XawTextPositionfrom, to;

   w
          Specifies the Text widget.

   from
          Specifies the start of the text to redisplay.

   to
          Specifies the end of the text to redisplay.

   See section 5.4 for a description of XawTextPosition. The
   XawTextInvalidate function causes the specified range of
   characters to be redisplayed immediately if redisplay is
   enabled or the next time that redisplay is enabled.

   To enable redisplay, use XawTextEnableRedisplay:
   void XawTextEnableRedisplay( w);
   Widget w;

   w
          Specifies the Text widget.

   The XawTextEnableRedisplay function flushes any changes due to
   batched updates when XawTextDisableRedisplay was called and
   allows future changes to be reflected immediately.

   To disable redisplay while making several changes, use
   XawTextDisableRedisplay.
   void XawTextDisableRedisplay( w);
   Widget w;

   w
          Specifies the Text widget.

   The XawTextDisableRedisplay function causes all changes to be
   batched until either XawTextDisplay or XawTextEnableRedisplay
   is called.

   To display batched updates, use XawTextDisplay:
   void XawTextDisplay( w);
   Widget w;

   w
          Specifies the Text widget.

   The XawTextDisplay function forces any accumulated updates to
   be displayed.

Resources Convenience Routines

   To obtain the character position of the left-most character on
   the first line displayed in the widget (the value of the
   displayPosition resource), use XawTextTopPosition.
   XawTextPosition XawTextTopPosition( w);
   Widget w;

   w
          Specifies the Text widget.

   To assign a new selection array to a text widget use
   XawTextSetSelectionArray:
   void XawTextSetSelectionArray( w,
                                  sarray);
   Widget w;
   XawTextSelectType* sarray;

   w
          Specifies the Text widget.

   sarray
          Specifies a selection array as defined in the section
          called \fBText Selections for Application
          Programmers\fP.

   Calling this function is equivalent to setting the value of the
   selectionTypes resource.

   To move the insertion point to the specified source position,
   use XawTextSetInsertionPoint:
   void XawTextSetInsertionPoint( w,
                                  position);
   Widget w;
   XawTextPosition position;

   w
          Specifies the Text widget.

   position
          Specifies the new position for the insertion point.

   See section 5.4 for a description of XawTextPosition. The text
   will be scrolled vertically if necessary to make the line
   containing the insertion point visible. Calling this function
   is equivalent to setting the insertPosition resource.

   To obtain the current position of the insertion point, use
   XawTextGetInsertionPoint:
   XawTextPosition XawTextGetInsertionPoint( w);
   Widget w;

   w
          Specifies the Text widget.

   See section 5.4 for a description of XawTextPosition. The
   result is equivalent to retrieving the value of the
   insertPosition resource.

   To replace the text source in the specified widget, use
   XawTextSetSource:
   void XawTextSetSource( w,
                          source,
                          position);
   Widget w;
   Widget source;
   XawTextPosition position;

   w
          Specifies the Text widget.

   source
          Specifies the text source object.

   position
          Specifies character position that will become the upper
          left hand corner of the displayed text. This is usually
          set to zero.

   See section 5.4 for a description of XawTextPosition. A display
   update will be performed if redisplay is enabled.

   To obtain the current text source for the specified widget, use
   XawTextGetSource:
   Widget XawTextGetSource( w);
   Widget w;

   w
          Specifies the Text widget.

   This function returns the text source that this Text widget is
   currently using.

   To enable and disable the insertion point, use
   XawTextDisplayCaret:
   void XawTextDisplayCaret( w,
                             visible);
   Widget w;
   Boolean visible;

   w
          Specifies the Text widget.

   visible
          Specifies whether or not the caret should be displayed.

   If visible is False the insertion point will be disabled. The
   marker is re-enabled either by setting visible to True, by
   calling XtSetValues, or by executing the display-caret action
   routine.

Customizing the Text Widget

   The remainder of this chapter will describe customizing the
   Text widget. The Text widget may be customized by subclassing,
   or by creating new sources and sinks. Subclassing is described
   in detail in Chapter 7; this section will describe only those
   things that are specific to the Text widget. Attributes of the
   Text widget base class and creating new sources and sinks will
   be discussed.

   The Text widget is made up of a number of different pieces,
   with the Text widget as the base widget class. It and the
   AsciiText widget are the only true "widgets" in the Text widget
   family. The other pieces (sources and sinks) are X Toolkit
   objects and have no window associated with them. No source or
   sink is useful unless assigned to a Text widget.

   Each of the following pieces of the Text widget has a specific
   purpose, and will be, or has been, discussed in detail in this
   chapter:

   Text
          This is the glue that binds everything else together.
          This widget reads the text data from the source, and
          displays the information in the sink. All translations
          and actions are handled in the Text widget itself.

   TextSink
          This object is responsible for displaying and clearing
          the drawing area. It also reports the configuration of
          the window that contains the drawing area. The TextSink
          does not have its own window; instead it does its
          drawing on the Text widget's window.

   TextSrc
          This object is responsible for reading, editing and
          searching through the text buffer.

   AsciiSink
          This object is a subclass of the TextSink and knows how
          to display ASCII text. Support has been added to display
          any 8-bit character set, given the font.

   MultiSink
          This object is a subclass of the TextSink and knows how
          to display font sets.

   AsciiSrc
          This object is a subclass of the TextSrc and knows how
          to read strings and files.

   MultiSrc
          This object is a subclass of the TextSrc and knows how
          to read strings and multibyte files, converting them to
          wide characters based on locale.

   AsciiText
          This widget is a subclass of the Text widget. When
          created, the AsciiText automatically creates and
          attaches either an AsciiSrc and AsciiSink, or a MultiSrc
          and MultiSink, to itself. The AsciiText provides the
          simplest interface to the Athena Text widgets.

Text Widget

Application Header file     <X11/Xaw/Text.h>
Class Header file           <X11/Xaw/TextP.h>
Class                       textWidgetClass
Class Name                  Text
Superclass                  Simple

   The Text widget is the glue that binds all the other pieces
   together, it maintains the internal state of the displayed
   text, and acts as a mediator between the source and sink.

   This section lists the resources that are actually part of the
   Text widget, and explains the functionality provided by each.

Resources

   When creating a Text widget instance, the following resources
   are retrieved from the argument list or from the resource
   database:
   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   autoFill AutoFill Boolean   False
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   bottomMargin Margin Position   2
   colormap Colormap Colormap   Parent's Colormap
   cursor Cursor Cursor   XC_xterm
   cursorName Cursor String   NULL
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   displayCaret Output Boolean   True
   displayPosition TextPosition XawTextPosition   0
   height Height Dimension A Font height + margins
   insensitiveBorder Insensitive Pixmap   GreyPixmap
   insertPosition TextPosition int   0
   leftMargin Margin Position   2
   mappedWhenManaged MappedWhenManaged Boolean   True
   pointerColor Foreground Pixel   XtDefaultForeground
   pointerColorBackground Background Pixel   XtDefaultBackground
   resize Resize XawTextResizeMode   XawtextResizeNever
   rightMargin Margin Position   4
   screen Screen Pointer R Parent's Screen
   scrollHorizontal Scroll ScrollMode   XawtextScrollNever
   scrollVertical Scroll XawTextScrollMode   XawtextScrollNever
   selectTypes SelectTypes XawTextSelectType*   See above
   sensitive Sensitive Boolean   True
   textSink TextSink Widget   NULL
   textSource TextSource Widget   NULL
   topMargin Margin Position   2
   translations Translations TranslationTable   See above
   unrealizeCallback Callback XtCallbackList   NULL
   width Width Dimension   100
   wrap Wrap WrapMode   XawtextWrapNever
   x Position Position   0
   y Position Position   0

TextSink Object



Application Header file <X11/Xaw/TextSink.h>

Class Header file       <X11/Xaw/TextSinkP.h>

Class           textSinkObjectClass

Class Name      TextSink

Superclass      Object

   The TextSink object is the root object for all text sinks. Any
   new text sink objects should be subclasses of the TextSink
   Object. The TextSink Class contains all methods that the Text
   widget expects a text sink to export.

   Since all text sinks will have some resources in common, the
   TextSink defines a few new resources.

Resources

   When creating an TextSink object instance, the following
   resources are retrieved from the argument list or from the
   resource database:

        Name         Class         Type      Notes    Default Value
     background    Background     Pixel            XtDefaultBackground
   destroyCallback  Callback  XtCallbackList              NULL
     foreground    Foreground     Pixel            XtDefaultForeground
          _

Subclassing the TextSink

   The only purpose of the TextSink Object is to be subclassed. It
   contains the minimum set of class methods that all text sinks
   must have. While all may be inherited, the direct descendant of
   TextSink must specify some of them as TextSink does contain
   enough information to be a valid text sink by itself. Do not
   try to use the TextSink as a valid sink for the Text widget; it
   is not intended to be used as a sink by itself.
   Function Inherit with Public Interface must specify
   DisplayText XtInheritDisplayText XawTextSinkDisplayText yes
   InsertCursor XtInheritInsertCursor XawTextSinkInsertCursor yes
   ClearToBackground XtInheritClearToBackground
   XawTextSinkClearToBackground no
   FindPosition XtInheritFindPosition XawTextSinkFindPosition yes
   FindDistance XtInheritFindDistance XawTextSinkFindDistance yes
   Resolve XtInheritResolve XawTextSinkResolve yes
   MaxLines XtInheritMaxLines XawTextSinkMaxLines no
   MaxHeight XtInheritMaxHeight XawTextSinkMaxHeight no
   SetTabs XtInheritSetTabs XawTextSinkSetTabs no
   GetCursorBounds XtInheritGetCursorBounds
   XawTextSinkGetCursorBounds yes

Displaying Text

   To display a section of the text buffer contained in the text
   source use the function DisplayText:
   void DisplayText( w,
                     y,
                     pos2,
                     highlight);
   Widget w;
   Positionx, y;
   XawTextPositionpos1, pos2;
   Boolean highlight;

   w
          Specifies the TextSink object.

   x
          Specifies the x location to start drawing the text.

   y
          Specifies the y location to start drawing text.

   pos1
          Specifies the location within the text source of the
          first character to be printed.

   pos2
          Specifies the location within the text source of the
          last character to be printed.

   highlight
          Specifies whether or not to paint the text region
          highlighted.

   The Text widget will only pass one line at a time to the text
   sink, so this function does not need to know how to line feed
   the text. It is acceptable for this function to just ignore
   Carriage Returns. x and y denote the upper left hand corner of
   the first character to be displayed.

Displaying the Insert Point

   The function that controls the display of the text cursor is
   InsertCursor. This function will be called whenever the text
   widget desires to change the state of, or move the insert
   point.
   void InsertCursor( w,
                      y,
                      state);
   Widget w;
   Positionx, y;
   XawTextInsertState state;

   w
          Specifies the TextSink object.

   x
          Specifies the x location of the cursor in Pixels.

   y
          Specifies the y location of the cursor in Pixels.

   state
          Specifies the state of the cursor, may be one of XawisOn
          or XawisOff.

   X and y denote the upper left hand corner of the insert point.

Clearing Portions of the Text window

   To clear a portion of the Text window to its background color,
   the Text widget will call ClearToBackground. The TextSink
   object already defines this function as calling XClearArea on
   the region passed. This behavior will be used if you specify
   XtInheritClearToBackground for this method.
   void ClearToBackground( w,
                           y,
                           height);
   Widget w;
   Positionx, y;
   Dimensionwidth, height;

   w
          Specifies the TextSink object.

   x
          Specifies the x location, in pixels, of the Region to
          clear.

   y
          Specifies the y location, in pixels, of the Region to
          clear.

   width
          Specifies the width, in pixels, of the Region to clear.

   height
          Specifies the height, in pixels, of the Region to clear.

   X and y denote the upper left hand corner of region to clear.

Finding a Text Position Given Pixel Values

   To find the text character position that will be rendered at a
   given x location the Text widget uses the function
   FindPosition:
   void FindPosition( w,
                      fromPos,
                      width,
                      stopAtWordBreak,
                      *pos_return,
                      *height_return);
   Widget w;
   XawTextPosition fromPos;
   intfromX, width;
   Boolean stopAtWordBreak;
   XawTextPosition *pos_return;
   int*width_return, *height_return;

   w
          Specifies the TextSink object.

   fromPos
          Specifies a reference position, usually the first
          character in this line. This character is always to the
          left of the desired character location.

   fromX
          Specifies the distance that the left edge of fromPos is
          from the left edge of the window. This is the reference
          x location for the reference position.

   width
          Specifies the distance, in pixels, from the reference
          position to the desired character position.

   stopAtWordBreak
          Specifies whether or not the position that is returned
          should be forced to be on a word boundary.

   pos_return
          Returns the character position that corresponds to the
          location that has been specified, or the work break
          immediately to the left of the position if
          stopAtWordBreak is True.

   width_return
          Returns the actual distance between fromPos and
          pos_return.

   height_return
          Returns the maximum height of the text between fromPos
          and pos_return.

   This function need make no attempt to deal with line feeds. The
   text widget will only call it one line at a time.

   Another means of finding a text position is provided by the
   Resolve function:
   void Resolve( w,
                 fromPos,
                 width,
                 *pos_return);
   Widget w;
   XawTextPosition fromPos;
   intfromX, width;
   XawTextPosition *pos_return;

   w
          Specifies the TextSink object.

   fromPos
          Specifies a reference position, usually the first
          character in this line. This character is always to the
          left of the desired character location.

   fromX
          Specifies the distance that the left edge of fromPos is
          from the left edge of the window. This is the reference
          x location for the reference position.

   width
          Specifies the distance, in pixels, from the reference
          position to the desired character position.

   pos_return
          Returns the character position that corresponds to the
          location that has been specified, or the word break
          immediately to the left if stopAtWordBreak is True.

   This function need make no attempt to deal with line feeds. The
   text widget will only call it one line at a time. This is a
   more convenient interface to the FindPosition function, and
   provides a subset of its functionality.

Finding the Distance Between two Text Positions

   To find the distance in pixels between two text positions on
   the same line use the function FindDistance.
   void FindDistance( w,
                      toPos,
                      fromX,
                      *pos_return,
                      *height_return);
   Widget w;
   XawTextPositionfromPos, toPos;
   int fromX;
   XawTextPosition *pos_return;
   int*width_return, *height_return;

   w
          Specifies the TextSink object.

   fromPos
          Specifies the text buffer position, in characters, of
          the first position.

   fromX
          Specifies the distance that the left edge of fromPos is
          from the left edge of the window. This is the reference
          x location for the reference position.

   toPos
          Specifies the text buffer position, in characters, of
          the second position.

   resWidth
          Return the actual distance between fromPos and
          pos_return.

   resPos
          Returns the character position that corresponds to the
          actual character position used for toPos in the
          calculations. This may be different than toPos, for
          example if fromPos and toPos are on different lines in
          the file.

   height_return
          Returns the maximum height of the text between fromPos
          and pos_return.

   This function need make no attempt to deal with line feeds. The
   Text widget will only call it one line at a time.

Finding the Size of the Drawing area

   To find the maximum number of lines that will fit into the
   current Text widget, use the function MaxLines. The TextSink
   already defines this function to compute the maximum number of
   lines by using the height of font.
   int MaxLines( w,
                 height);
   Widget w;
   Dimension height;

   w
          Specifies the TextSink object.

   height
          Specifies the height of the current drawing area.

   Returns the maximum number of lines that will fit in height.

   To find the height required for a given number of text lines,
   use the function MaxHeight. The TextSink already defines this
   function to compute the maximum height of the window by using
   the height of font.
   int MaxHeight( w,
                  lines);
   Widget w;
   int lines;

   w
          Specifies the TextSink object.

   height
          Specifies the height of the current drawing area.

   Returns the height that will be taken up by the number of lines
   passed.

Setting the Tab Stops

   To set the tab stops for a text sink use the SetTabs function.
   The TextSink already defines this function to set the tab x
   location in pixels to be the number of characters times the
   figure width of font.
   void SetTabs( w,
                 *tabs);
   Widget w;
   inttab_count, *tabs;

   w
          Specifies the TextSink object.

   tab_count
          Specifies the number of tabs passed in tabs.

   tabs
          Specifies the position, in characters, of the tab stops.

   This function is responsible for the converting character
   positions passed to it into whatever internal positions the
   TextSink uses for tab placement.

Getting the Insert Point's Size and Location

   To get the size and location of the insert point use the
   GetCursorBounds function.
   void GetCursorBounds( w,
                         *rect_return);
   Widget w;
   XRectangle *rect_return;

   w
          Specifies the TextSinkObject.

   rect_return
          Returns the location and size of the insert point.

   Rect will be filled with the current size and location of the
   insert point.

TextSrc Object

Application Header file <X11/Xaw/TextSrc.h>
Class Header file       <X11/Xaw/TextSrcP.h>
Class                   textSrcObjectClass
Class Name              TextSrc
Superclass              Object

   The TextSrc object is the root object for all text sources. Any
   new text source objects should be subclasses of the TextSrc
   Object. The TextSrc Class contains all methods the Text widget
   expects a text source to export.

   Since all text sources will have some resources in common the
   TextSrc defines a few new resources.

Resources

   When creating an TextSrc object instance, the following
   resources are retrieved from the argument list or from the
   resource database:
        Name        Class        Type      Notes Default Value
   destroyCallback Callback XtCallbackList           NULL
      editType     EditType    EditMode              NULL

Subclassing the TextSrc

   The only purpose of the TextSrc Object is to be subclassed. It
   contains the minimum set of class methods that all text sources
   must have. All class methods of the TextSrc must be defined, as
   the Text widget uses them all. While all may be inherited, the
   direct descendant of TextSrc must specify some of them as
   TextSrc does not contain enough information to be a valid text
   source by itself. Do not try to use the TextSrc as a valid
   source for the Text widget; it is not intended to be used as a
   source by itself and bad things will probably happen.
   Function Inherit with Public Interface must specify
   Read XtInheritRead XawTextSourceRead yes
   Replace XtInheritReplace XawTextSourceReplace no
   Scan XtInheritScan XawTextSourceScan yes
   Search XtInheritSearch XawTextSourceSearch no
   SetSelection XtInheritSetSelection XawTextSourceSetSelection no
   ConvertSelection XtInheritConvertSelection
   XawTextSourceConvertSelection no

Reading Text.

   To read the text in a text source use the Read function:
   XawTextPosition Read( w,
                         pos,
                         *text_return,
                         length);
   Widget w;
   XawTextPosition pos;
   XawTextBlock *text_return;
   int length;

   w
          Specifies the TextSrc object.

   pos
          Specifies the position of the first character to be read
          from the text buffer.

   text
          Returns the text read from the source.

   length
          Specifies the maximum number of characters the TextSrc
          should return to the application in text_return.

   This function returns the text position immediately after the
   characters read from the text buffer. The function is not
   required to read length characters if that many characters are
   in the file, it may break at any point that is convenient to
   the internal structure of the source. It may take several calls
   to Read before the desired portion of the text buffer is fully
   retrieved.

Replacing Text.

   To replace or edit the text in a text buffer use the Replace
   function:
   XawTextPosition Replace( w,
                            end,
                            *text);
   Widget w;
   XawTextPositionstart, end;
   XawTextBlock *text;

   w
          Specifies the TextSrc object.

   start
          Specifies the position of the first character to be
          removed from the text buffer. This is also the location
          to begin inserting the new text.

   end
          Specifies the position immediately after the last
          character to be removed from the text buffer.

   text
          Specifies the text to be added to the text source.

   This function can return any of the following values:

   XawEditDone
          The text replacement was successful.

   XawPositionError
          The edit mode is XawtextAppend and start is not the last
          character of the source.

   XawEditError
          Either the Source was read-only or the range to be
          deleted is larger than the length of the Source.

   The Replace arguments start and end represent the text source
   character positions for the existing text that is to be
   replaced by the text in the text block. The characters from
   start up to but not including end are deleted, and the buffer
   specified by the text block is inserted in their place. If
   start and end are equal, no text is deleted and the new text is
   inserted after start.

Scanning the TextSrc

   To search the text source for one of the predefined boundary
   types use the Scan function:
   XawTextPosition Scan( w,
                         position,
                         type,
                         dir,
                         count,
                         include);
   Widget w;
   XawTextPosition position;
   XawTextScanType type;
   XawTextScanDirection dir;
   int count;
   Boolean include;

   w
          Specifies the TextSrc object.

   position
          Specifies the position to begin scanning the source.

   type
          Specifies the type of boundary to scan for, may be one
          of: XawstPosition, XawstWhiteSpace, XawstEOL,
          XawstParagraph, XawstAll. The exact meaning of these
          boundaries is left up to the individual text source.

   dir
          Specifies the direction to scan, may be either XawsdLeft
          to search backward, or XawsdRight to search forward.

   count
          Specifies the number of boundaries to scan for.

   include
          Specifies whether the boundary itself should be included
          in the scan.

   The Scan function returns the position in the text source of
   the desired boundary. It is expected to return a valid address
   for all calls made to it, thus if a particular request is made
   that would take the text widget beyond the end of the source it
   must return the position of that end.

Searching through a TextSrc

   To search for a particular string use the Search function.
   XawTextPosition Search( w,
                           position,
                           dir,
                           *text);
   Widget w;
   XawTextPosition position;
   XawTextScanDirection dir;
   XawTextBlock *text;

   w
          Specifies the TextSrc object.

   position
          Specifies the position to begin the search.

   dir
          Specifies the direction to search, may be either
          XawsdLeft to search backward, or XawsdRight to search
          forward.

   text
          Specifies a text block containing the text to search
          for.

   This function will search through the text buffer attempting to
   find a match for the string in the text block. If a match is
   found in the direction specified, then the character location
   of the first character in the string is returned. If no text
   was found then XawTextSearchError is returned.

Text Selections

   While many selection types are handled by the Text widget, text
   sources may have selection types unknown to the Text widget.
   When a selection conversion is requested by the X server the
   Text widget will first call the ConvertSelection function, to
   attempt the selection conversion.
   Boolean ConvertSelections( w,
                              *type,
                              *value_return,
                              *length_return,
                              *format_return);
   Widget w;
   Atom*selection,*target, *type;
   caddr_t *value_return;
   unsignedlong *length_return;
   int *format_return;

   w
          Specifies the TextSrc object.

   selection
          Specifies the type of selection that was requested (e.g.
          PRIMARY).

   target
          Specifies the type of the selection that has been
          requested, which indicates the desired information about
          the selection (e.g. Filename, Text, Window).

   type
          Specifies a pointer to the atom into which the property
          type of the converted value of the selection is to be
          stored. For instance, either file name or text might
          have property type XA_STRING.

   value_return
          Returns a pointer into which a pointer to the converted
          value of the selection is to be stored. The selection
          owner is responsible for allocating this storage. The
          memory is considered owned by the toolkit, and is freed
          by XtFree when the Intrinsics selection mechanism is
          done with it.

   length_return
          Returns a pointer into which the number of elements in
          value is to be stored. The size of each element is
          determined by format.

   format_return
          Returns a pointer into which the size in bits of the
          data elements of the selection value is to be stored.

   If this function returns True then the Text widget will assume
   that the source has taken care of converting the selection,
   Otherwise the Text widget will attempt to convert the selection
   itself.

   If the source needs to know when the text selection is modified
   it should define a SetSelection procedure:
   void SetSelection( w,
                      end,
                      selection);
   Widget w;
   XawTextPositionstart, end;
   Atom selection;

   w
          Specifies the TextSrc object.

   start
          Specifies the character position of the beginning of the
          new text selection.

   end
          Specifies the character position of the end of the new
          text selection.

   selection
          Specifies the type of selection that was requested (e.g.
          PRIMARY).

Ascii Sink Object and Multi Sink Object



Application Header file <X11/Xaw/AsciiSink.h>

Class Header file       <X11/Xaw/AsciiSinkP.h>

Class           asciiSinkObjectClass

Class Name      AsciiSink

Superclass      TextSink

   The AsciiSink or MultiSink object is used by a text widget to
   render the text. Depending on its international resource, a
   AsciiText widget will create one or the other of these when the
   AsciiText itself is created. Both types are nearly identical;
   the following discussion applies to both, with MultiSink
   differences noted only as they occur. The AsciiSink will
   display all printing characters in an 8 bit font, along with
   handling Tab and Carriage Return. The name has been left as
   ``AsciiSink'' for compatibility. \fIThe MultiSink will display
   all printing characters in a font set, along with handling Tab
   and Carriage Return.\fP The source object also reports the text
   window metrics to the text widgets.

Resources

   When creating an AsciiSink object instance, the following
   resources are retrieved from the argument list or from the
   resource database:

         Name          Class         Type      Notes    Default Value
      background     Background     Pixel            XtDefaultBackground
   destroyCallback    Callback  XtCallbackList              NULL
  displayNonprinting   Output      Boolean                  True
         echo          Output      Boolean                  True
         font           Font     XFontStruct*           XtDefaultFont
       fontSet        FontSet      XFontSet           XtDefaultFontSet
      foreground     Foreground     Pixel            XtDefaultForeground
          _

   This resource is retrieved by the AsciiSink instead of being
   copied from the Text widget.

   The text font to use when displaying the string. (This resource
   is present in the AsciiSink, but not the MultiSink.)

   The text font set to use when displaying the string. (This
   resource is present in the MultiSink, but not the AsciiSink.)

Ascii Source Object and Multi Source Object



Application Header file <X11/Xaw/AsciiSrc.h> or <X11/Xaw/MultiSrc.h>

Class Header file       <X11/Xaw/AsciiSrcP.h> or  <X11/Xaw/MultiSrcP.h>

Class           asciiSrcObjectClass or multiSrcObjectClass

Class Name      AsciiSrc or MultiSrc

Superclass      TextSource

   The AsciiSrc or MultiSrc object is used by a text widget to
   read the text from a file or string in memory. Depending on its
   international resource, an AsciiText widget will create one or
   the other of these when the AsciiText itself is created. Both
   types are nearly identical; the following discussion applies to
   both, with MultiSrc differences noted only as they occur.

   The AsciiSrc understands all Latin1 characters plus Tab and
   Carriage Return. \fIThe MultiSrc understands any set of
   character sets that the underlying X implementation's
   internationalization handles.\fP

   The AsciiSrc can be either of two types: XawAsciiFile or
   XawAsciiString.

   AsciiSrc objects of type XawAsciiFile read the text from a file
   and store it into an internal buffer. This buffer may then be
   modified, provided the text widget is in the correct edit mode,
   just as if it were a source of type XawAsciiString. Unlike R3
   and earlier versions of the AsciiSrc, it is now possible to
   specify an editable disk source. The file is not updated,
   however, until a call to XawAsciiSave is made. When the source
   is in this mode the useStringInPlace resource is ignored.

   AsciiSrc objects of type XawAsciiString have the text buffer
   implemented as a string. \fIMultiSrc objects of type
   XawAsciiString have the text buffer implemented as a wide
   character string.\fP The string owner is responsible for
   allocating and managing storage for the string.

   In the default case for AsciiSrc objects of type
   XawAsciiString, the resource useStringInPlace is false, and the
   widget owns the string. The initial value of the string
   resource, and any update made by the application programmer to
   the string resource with XtSetValues, is copied into memory
   private to the widget, and managed internally by the widget.
   The application writer does not need to worry about running out
   of buffer space (subject to the total memory available to the
   application). The performance does not decay linearly as the
   buffer grows large, as is necessarily the case when the text
   buffer is used in place. The application writer must use
   XtGetValues to determine the contents of the text buffer, which
   will return a copy of the widget's text buffer as it existed at
   the time of the XtGetValues call. This copy is not affected by
   subsequent updates to the text buffer, i.e., it is not updated
   as the user types input into the text buffer. This copy is
   freed upon the next call to XtGetValues to retrieve the string
   resource; however, to conserve memory, there is a convenience
   routine, XawAsciiSourceFreeString, allowing the application
   programmer to direct the widget to free the copy.

   When the resource useStringInPlace is true and the AsciiSrc
   object is of type XawAsciiString, the application is the string
   owner. The widget will take the value of the string resource as
   its own text buffer, and the length resource indicates the
   buffer size. In this case the buffer contents change as the
   user types at the widget; it is not necessary to call
   XtGetValues on the string resource to determine the contents of
   the buffer-it will simply return the address of the
   application's implementation of the text buffer.

Resources

   When creating an AsciiSrc object instance, the following
   resources are retrieved from the argument list or from the
   resource database:

       Name            Class            Type      Notes  Default Value
     callback         Callback     XtCallbackList             NULL
 dataCompression  DataCompression     Boolean                 True
 destroyCallback      Callback        Callback                NULL
     editType         EditType        EditMode            XawtextRead
      length           Length           Int         A   length of string
    pieceSize        PieceSize          Int                  BUFSIZ
      string           String          String                 NULL
       type             Type         AsciiType           XawAsciiString
 useStringInPlace UseStringInPlace    Boolean                False
        _

Convenience Routines

   The AsciiSrc has a few convenience routines that allow the
   application programmer quicker or easier access to some of the
   commonly used functionality of the AsciiSrc.

Conserving Memory

   When the AsciiSrc widget is not in useStringInPlace mode space
   must be allocated whenever the file is saved, or the string is
   requested with a call to XtGetValues. This memory is allocated
   on the fly, and remains valid until the next time a string
   needs to be allocated. You may save memory by freeing this
   string as soon as you are done with it by calling
   XawAsciiSourceFreeString.
   void XawAsciiSourceFreeString( w);
   Widget w;

   w
          Specifies the AsciiSrc object.

   This function will free the memory that contains the string
   pointer returned by XtGetValues. This will normally happen
   automatically when the next call to XtGetValues occurs, or when
   the widget is destroyed.

Saving Files

   To save the changes made in the current text source into a file
   use XawAsciiSave.
   Boolean XawAsciiSave( w);
   Widget w;

   w
          Specifies the AsciiSrc object.

   XawAsciiSave returns True if the save was successful. It will
   update the file named in the string resource. If the buffer has
   not been changed, no action will be taken. This function only
   works on an AsciiSrc of type XawAsciiFile.

   To save the contents of the current text buffer into a named
   file use XawAsciiSaveAsFile.
   Boolean XawAsciiSaveAsFile( w,
                               name);
   Widget w;
   String name;

   w
          Specifies the AsciiSrc object.

   name
          The name of the file to save the current buffer into.

   This function returns True if the save was successful.
   XawAsciiSaveAsFile will work with a buffer of either type
   XawAsciiString or type XawAsciiFile.

Seeing if the Source has Changed

   To find out if the text buffer in an AsciiSrc object has
   changed since the last time it was saved with XawAsciiSave or
   queried use XawAsciiSourceChanged.
   Boolean XawAsciiSourceChanged( w);
   Widget w;

   w
          Specifies the AsciiSrc object.

   This function will return True if the source has changed since
   the last time it was saved or queried. The internal change flag
   is reset whenever the string is queried via XtGetValues or the
   buffer is saved via XawAsciiSave.

Ascii Text Widget



Application Header file <X11/Xaw/AsciiText.h>

ClassHeader file        <X11/Xaw/AsciiTextP.h>

Class           asciiTextWidgetClass

Class Name      Text

Superclass      Text
Sink Name       textSink
Source Name     textSource

   For the ease of internationalization, the AsciiText widget
   class name has not been changed, although it is actually able
   to support non-ASCII locales. The AsciiText widget is really a
   collection of smaller parts. It includes the Text widget
   itself, a ``Source'' (which supports memory management), and a
   ``Sink'' (which handles the display). There are currently two
   supported sources, the AsciiSrc and MultiSrc, and two supported
   sinks, the AsciiSink and MultiSink. Some of the resources
   listed below are not actually resources of the AsciiText, but
   belong to the associated source or sink. This is is noted in
   the explanation of each resource where it applies. When
   specifying these resources in a resource file it is necessary
   to use *AsciiText*resource_name instead of
   *AsciiText.resource_name, since they actually belong to the
   children of the AsciiText widget, and not the AsciiText widget
   itself. However, these resources may be set directly on the
   AsciiText widget at widget creation time, or via XtSetValues.

Resources

   When creating an AsciiText widget instance, the following
   resources are retrieved from the argument list or from the
   resource database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   autoFill AutoFill Boolean   False
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   bottomMargin Margin Position   2
   callback Callback XtCallbackList   NULL
   colormap Colormap Colormap   Parent's Colormap
   cursor Cursor Cursor   XC_xterm
   cursorName Cursor String   NULL
   dataCompression DataCompression Boolean   True
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   displayCaret Output Boolean   True
   displayNonprinting Output Boolean   True
   displayPosition TextPosition XawTextPosition   0
   echo Output Boolean   True
   editType EditType XawTextEditType   XawtextRead
   font Font XFontStruct*   XtDefaultFont
   fontSet FontSet XFontSet   XtDefaultFontSet
   foreground Foreground Pixel   XtDefaultForeground
   height Height Dimension A Font height + margins
   insensitiveBorder Insensitive Pixmap   GreyPixmap
   insertPosition TextPosition int   0
   international International Boolean C False
   leftMargin Margin Dimension   2
   length Length int A length of string
   mappedWhenManaged MappedWhenManaged Boolean   True
   pieceSize PieceSize XawTextPosition   BUFSIZ
   pointerColor Foreground Pixel   XtDefaultForeground
   pointerColorBackground Background Pixel   XtDefaultBackground
   resize Resize XawTextResizeMode   XawtextResizeNever
   rightMargin Margin Position   2
   screen Screen Screen R Parent's Screen
   scrollHorizontal Scroll XawTextScrollMode   XawtextScrollNever
   scrollVertical Scroll XawTextScrollMode   XawtextScrollNever
   selectTypes SelectTypes XawTextSelectType*   See above
   sensitive Sensitive Boolean   True
   string String String   NULL
   textSink TextSink Widget   An AsciiSink
   textSource TextSource Widget   An AsciiSrc
   topMargin Margin Position   2
   translations Translations TranslationTable   See above
   type Type XawAsciiType   XawAsciiString
   useStringInPlace UseStringInPlace Boolean   False
   width Width Dimension   100
   wrap Wrap WrapMode   XawtextWrapNever
   x Position Position   0
   y Position Position   0

Chapter 6. Composite and Constraint Widgets

   Table of Contents

   Box Widget

        Resources
        Layout Semantics

   Dialog Widget

        Resources
        Constraint Resources
        Layout Semantics
        Automatically Created Children.
        Convenience Routines

   Form Widget

        Resources
        Constraint Resources
        Layout Semantics
        Convenience Routines

   Paned Widget

        Using the Paned Widget
        Resources
        Constraint Resources
        Layout Semantics
        Grip Translations
        Convenience Routines

   Porthole Widget

        Resources
        Layout Semantics
        Porthole Callbacks

   Tree Widget

        Resources
        Constraint Resources
        Layout Semantics
        Convenience Routines

   Viewport Widget

        Resources
        Layout Semantics

   These widgets may contain arbitrary widget children. They
   implement a policy for the size and location of their children.

   Box
          This widget will pack its children as tightly as
          possible in non-overlapping rows.

   Dialog
          An implementation of a commonly used interaction
          semantic to prompt for auxiliary input from the user,
          such as a filename.

   Form
          A more sophisticated layout widget that allows the
          children to specify their positions relative to the
          other children, or to the edges of the Form.

   Paned
          Allows children to be tiled vertically or horizontally.
          Controls are also provided to allow the user to
          dynamically resize the individual panes.

   Porthole
          Allows viewing of a managed child which is as large as,
          or larger than its parent, typically under control of a
          Panner widget.

   Tree
          Provides geometry management of widgets arranged in a
          directed, acyclic graph.

   Viewport
          Consists of a frame, one or two scrollbars, and an inner
          window. The inner window can contain all the data that
          is to be displayed. This inner window will be clipped by
          the frame with the scrollbars controlling which section
          of the inner window is currently visible.

Note

   The geometry management semantics provided by the X Toolkit
   give full control of the size and position of a widget to the
   parent of that widget. While the children are allowed to
   request a certain size or location, it is the parent who makes
   the final decision. Many of the composite widgets here will
   deny any geometry request from their children by default. If a
   child widget is not getting the expected size or location, it
   is most likely the parent disallowing a request, or
   implementing semantics slightly different than those expected
   by the application programmer.

   If the application wishes to change the size or location of any
   widget it should make a call to XtSetValues. This will allow
   the widget to ask its parent for the new size or location. As
   noted above the parent is allowed to refuse this request, and
   the child must live with the result. If the application is
   unable to achieve the desired semantics, then perhaps it should
   use a different composite widget. Under no circumstances should
   an application programmer resort to XtMoveWidget or
   XtResizeWidget; these functions are exclusively for the use of
   Composite widget implementors.

   For more information on geometry management consult the X
   Toolkit Intrinsics - C Language Interface.

Box Widget




Application Header file <X11/Xaw/Box.h>

Class Header file       <X11/Xaw/BoxP.h>

Class           boxWidgetClass

Class Name      Box

Superclass      Composite


   The Box widget provides geometry management of arbitrary
   widgets in a box of a specified dimension. The children are
   rearranged when resizing events occur either on the Box or its
   children, or when children are managed or unmanaged. The Box
   widget always attempts to pack its children as tightly as
   possible within the geometry allowed by its parent.

   Box widgets are commonly used to manage a related set of
   buttons and are often called ButtonBox widgets, but the
   children are not limited to buttons. The Box's children are
   arranged on a background that has its own specified dimensions
   and color.

Resources

   When creating a Box widget instance, the following resources
   are retrieved from the argument list or from the resource
   database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   children ReadOnly WidgetList R NULL
   colormap Colormap Colormap   Parent's Colormap
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   height Height Dimension A see Layout Semantics
   hSpace HSpace Dimension   4
   mappedWhenManaged MappedWhenManaged Boolean   True
   numChildren ReadOnly Cardinal R 0
   orientation Orientation Orientation   XtorientVertical
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   vSpace VSpace Dimension   4
   translations Translations TranslationTable   NULL
   width Width Dimension A see Layout Semantics
   x Position Position   0
   y Position Position   0
   _

   hSpace

   vSpace
          The amount of space, in pixels, to leave between the
          children. This resource specifies the amount of space
          left between the outermost children and the edge of the
          box.

   orientation
          Specifies whether the preferred shape of the box (i.e.
          the result returned by the query_geometry class method)
          is tall and narrow XtorientVertical or short and wide
          XtorientHorizontal. When the Box is a child of a parent
          which enforces width constraints, it is usually better
          to specify XtorientVertical (the default). When the
          parent enforces height constraints, it is usually better
          to specify XtorientHorizontal.

Layout Semantics

   Each time a child is managed or unmanaged, the Box widget will
   attempt to reposition the remaining children to compact the
   box. Children are positioned in order left to right, top to
   bottom. The packing algorithm used depends on the orientation
   of the Box.

   XtorientVertical
          When the next child does not fit on the current row, a
          new row is started. If a child is wider than the width
          of the box, the box will request a larger width from its
          parent and will begin the layout process from the
          beginning if a new width is granted.

   XtorientHorizontal
          When the next child does not fit on the current row, the
          Box widens if possible (so as to keep children on a
          single row); otherwise a new row is started.

   After positioning all children, the Box widget attempts to
   shrink its own size to the minimum dimensions required for the
   layout.

Dialog Widget




Application Header file <X11/Xaw/Dialog.h>

Class Header file       <X11/Xaw/DialogP.h>

Class           dialogWidgetClass

Class Name      Dialog

Superclass      Form


   The Dialog widget implements a commonly used interaction
   semantic to prompt for auxiliary input from a user. For
   example, you can use a Dialog widget when an application
   requires a small piece of information, such as a filename, from
   the user. A Dialog widget, which is simply a special case of
   the Form widget, provides a convenient way to create a
   preconfigured form.

   The typical Dialog widget contains three areas. The first line
   contains a description of the function of the Dialog widget,
   for example, the string Filename:. The second line contains an
   area into which the user types input. The third line can
   contain buttons that let the user confirm or cancel the Dialog
   input. Any of these areas may be omitted by the application.

Resources

   When creating a Dialog widget instance, the following resources
   are retrieved from the argument list or the resource database:
   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   children ReadOnly WidgetList R NULL
   colormap Colormap Colormap   Parent's Colormap
   defaultDistance Thickness int   4
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   height Height Dimension A Enough space to contain all children
   icon Icon Bitmap   None
   label Label String   "label"
   mappedWhenManaged MappedWhenManaged Boolean   True
   numChildren ReadOnly Cardinal R 0
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   translations Translations TranslationTable   NULL
   value Value String   no value widget
   width Width Dimension A Enough space to contain all children
   x Position Position   0
   y Position Position   0
   _

   icon
          A pixmap image to be displayed immediately to the left
          of the Dialog widget's label.

   label
          A string to be displayed at the top of the Dialog
          widget.

   value
          An initial value for the string field that the user will
          enter text into. By default, no text entry field is
          available to the user. Specifying an initial value for
          value activates the text entry field. If string input is
          desired, but no initial value is to be specified then
          set this resource to "" (empty string).

Constraint Resources

   Each child of the Dialog widget may request special layout
   resources be applied to it. These constraint resources allow
   the Dialog widget's children to specify individual layout
   requirements.

       Name        Class      Type     Notes       Default Value
      bottom       Edge    XawEdgeType               XawRubber
     fromHoriz    Widget     Widget          NULL (left edge of Dialog)
     fromVert     Widget     Widget          NULL (top edge of Dialog)
   horizDistance Thickness     int            defaultDistance resource
       left        Edge    XawEdgeType               XawRubber
     resizable    Boolean    Boolean                   FALSE
       right       Edge    XawEdgeType               XawRubber
        top        Edge    XawEdgeType               XawRubber
   vertDistance  Thickness     int            defaultDistance resource

bottom
left
right
top            What to do with this edge of the child when
               the parent is resized.  This resource may be
               any edgeType.  See Layout Semantics for
               details.

fromHoriz
fromVert       Which widget this child should be placed
               underneath (or to the right of).  If a value
               of NULL is specified then this widget will be
               positioned relative to the edge of the par-
               ent.

horizDistance
vertDistance   The amount of space, in pixels, between this
               child and its left or upper neighbor.

resizable      If this resource is False then the parent
               widget will ignore all geometry request made
               by this child.  The parent may still resize
               this child itself, however.

Layout Semantics

   The Dialog widget uses two different sets of layout seman-
   tics. One is used when initially laying out the children. The
   other is used when the Dialog is resized.

   The first layout method uses the fromVert mand fromHoriz
   resources to place the children of the Dialog. A single pass is
   made through the Dialog widget's children in the order that
   they were created. Each child is then placed in the Dialog
   widget below or to the right of the widget speci- fied by the
   fromVert mand fromHoriz mresources. The distance the new child
   is placed from its left or upper neighbor is determined by the
   horizDistance mand vertDistance mresources. This implies some
   things about how the order of creation affects the possible
   placement of the children. The Form widget registers a string
   to widget converter which does not postpone conversion and does
   not cache conversion results.

   The second layout method is used when the Dialog is resized. It
   does not matter what causes this resize, and it is possi- ble
   for a resize to happen before the widget becomes visible (due
   to constraints imposed by the parent of the Dialog). This
   layout method uses the bottom , top , left , and right
   resources. These resources are used to determine what will
   happen to each edge of the child when the Dialog is resized. If
   a value of XawChain <something> is specified, the the edge of
   the child will remain a fixed distance from the chain edge of
   the Dialog. For example if XawChainLeft mis specified for the
   right mresource of a child then the right edge of that child
   will remain a fixed distance from the left edge of the Dialog
   widget. If a value of XawRubber mis spec- ified, that edge will
   grow by the same percentage that the Dialog grew. For instance
   if the Dialog grows by 50% the left edge of the child (if
   specified as XawRubber mwill be 50% farther from the left edge
   of the Dialog). One must be very careful when specifying these
   resources, for when they are specified incorrectly children may
   overlap or completely occlude other children when the Dialog
   widget is resized.

   Edge Type Resource Name Description
   XawChainBottom ChainBottom Edge remains a fixed distance from
   bottom of Dialog
   XawChainLeft ChainLeft Edge remains a fixed distance from left
   of Dialog
   XawChainRight ChainRight Edge remains a fixed distance from
   right of Dialog
   XawChainTop ChainTop Edge remains a fixed distance from top of
   Dialog
   XawRubber Rubber Edges will move a proportional distance

Example

   If you wish to force the Dialog to never resize one or more of
   its children then set left and right to XawChainLeft and top
   and bottom to XawChainTop. This will cause the child to remain
   a fixed distance from the top and left edges of the Dialog, and
   to never resize.

Special Considerations

   The Dialog widget automatically sets the top and bottom
   resources for all Children that are subclasses of the Command
   widget, as well as the widget children that are used to contain
   the label, value, and icon. This policy allows the buttons at
   the bottom of the Dialog to interact correctly with the
   predefined children, and makes it possible for a client to
   simply create and manage a new Command button without having to
   specify its constraints.

   The Dialog will also set fromLeft to the last button in the
   Dialog for each new button added to the Dialog widget.

   The automatically added constraints cannot be overridden, as
   they are policy decisions of the Dialog widget. If a more
   flexible Dialog is desired, the application is free to use the
   Form widget to create its own Dialog policy.

Automatically Created Children.

   The Dialog uses Label widgets to contain the label and icon.
   These widgets are named label and icon respectively. The Dialog
   value is contained in an AsciiText widget whose name is value.
   Using XtNameToWidget the application can change those resources
   associated with each of these widgets that are not available
   through the Dialog widget itself.

Convenience Routines

   To return the character string in the text field, use
   String XawDialogGetValueString( w);
   Widget w;

   w
          Specifies the Dialog widget.

   This function returns a copy of the value string of the Dialog
   widget. This string is allocated by the AsciiText widget and
   will remain valid and unchanged until another call to
   XawDialogGetValueString or an XtGetValues call on the value
   widget, when the string will be automatically freed, and a new
   string is returned. This string may be freed earlier by calling
   the function XawAsciiSourceFreeString.

   To add a new button to the Dialog widget use
   XawDialogAddButton.
   void XawDialogAddButton( w,
                            name,
                            func,
                            client_data);
   Widget w;
   String name;
   XtCallbackProc func;
   XtPointer client_data;

   w
          Specifies the Dialog widget.

   name
          Specifies the name of the new Command button to be added
          to the Dialog.

   func
          Specifies a callback function to be called when this
          button is activated. If NULL is specified then no
          callback is added.

   client_data
          Specifies the client_data to be passed to the func.

   This function is merely a shorthand for the code sequence:



{
        Widget button = XtCreateManagedWidget(name, commandWidgetClass,
w, NULL, ZERO);
        XtAddCallback(button, XtNcallback, func, client_data);
}


Form Widget




Application Header file <X11/Xaw/Form.h>

Class Header file       <X11/Xaw/FormP.h>

Class           formWidgetClass

Class Name      Form

Superclass      Constraint


   The Form widget can contain an arbitrary number of children or
   subwidgets. The Form provides geometry management for its
   children, which allows individual control of the position of
   each child. Any combination of children can be added to a Form.
   The initial positions of the children may be computed relative
   to the positions of previously created children. When the Form
   is resized, it computes new positions and sizes for its
   children. This computation is based upon information provided
   when a child is added to the Form.

   The default width of the Form is the minimum width needed to
   enclose the children after computing their initial layout, with
   a margin of defaultDistance at the right and bottom edges. If a
   width and height is assigned to the Form that is too small for
   the layout, the children will be clipped by the right and
   bottom edges of the Form.

Resources

   When creating a Form widget instance, the following resources
   are retrieved from the argument list or from the resource
   database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   children ReadOnly WidgetList R NULL
   colormap Colormap Colormap   Parent's Colormap
   defaultDistance Thickness int   4
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   height Height Dimension A Enough space to contain all children
   mappedWhenManaged MappedWhenManaged Boolean   True
   numChildren ReadOnly Cardinal R 0
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   translations Translations TranslationTable   NULL
   width Width Dimension A Enough space to contain all children
   x Position Position   0
   y Position Position   0
   _

Constraint Resources

   Each child of the Form widget may request special layout
   resources be applied to it. These constraint resources allow
   the Form widget's children to specify individual layout
   requirements.

       Name        Class      Type     Notes      Default Value
      bottom       Edge    XawEdgeType              XawRubber
     fromHoriz    Widget     Widget          NULL (left edge of Form)
     fromVert     Widget     Widget          NULL (top edge of Form)
   horizDistance Thickness     int           defaultDistance resource
       left        Edge    XawEdgeType              XawRubber
     resizable    Boolean    Boolean                  FALSE
       right       Edge    XawEdgeType              XawRubber
        top        Edge    XawEdgeType              XawRubber
   vertDistance  Thickness     int           defaultDistance resource

bottom
left
right
top            What to do with this edge of the child when
               the parent is resized.  This resource may be
               any edgeType.  See Layout Semantics for
               details.

fromHoriz
fromVert       Which widget this child should be placed
               underneath (or to the right of).  If a value
               of NULL is specified then this widget will be
               positioned relative to the edge of the par-
               ent.

horizDistance
vertDistance   The amount of space, in pixels, between this
               child and its left or upper neighbor.

resizable      If this resource is False then the parent
               widget will ignore all geometry request made
               by this child.  The parent may still resize
               this child itself, however.

Layout Semantics

   The Form widget uses two different sets of layout semantics.
   One is used when initially laying out the children. The other
   is used when the Form is resized.

   The first layout method uses the fromVert and fromHoriz
   resources to place the children of the Form. A single pass is
   made through the Form widget's children in the order that they
   were created. Each child is then placed in the Form widget
   below or to the right of the widget specified by the fromVert
   and fromHoriz resources. The distance the new child is placed
   from its left or upper neighbor is deter- mined by the
   horizDistance and vertDistance resources. This implies some
   things about how the order of creation affects the possible
   placement of the children. The Form widget registers a string
   to widget converter which does not post- pone conversion and
   does not cache conversion results.

   The second layout method is used when the Form is resized. It
   does not matter what causes this resize, and it is possi- ble
   for a resize to happen before the widget becomes visible (due
   to constraints imposed by the parent of the Form). This layout
   method uses the bottom, top, left, and right resources. These
   resources are used to determine what will happen to each edge
   of the child when the Form is resized. If a value of XawChain
   <something> is specified, the the edge of the child will remain
   a fixed distance from the chain edge of the Form. For example
   if XawChainLeft is specified for the right resource of a child
   then the right edge of that child will remain a fixed distance
   from the left edge of the Form widget. If a value of XawRubber
   is specified, that edge will grow by the same percentage that
   the Form grew. For instance if the Form grows by 50% the left
   edge of the child (if specified as XawRubber will be 50%
   farther from the left edge of the Form). One must be very
   careful when specifying these resources, for when they are
   specified incorrectly children may overlap or completely
   occlude other children when the Form widget is resized.

   Edge Type Resource Name Description
   XawChainBottom ChainBottom Edge remains a fixed distance from
   bottom of Form
   XawChainLeft ChainLeft Edge remains a fixed distance from left
   of Form
   XawChainRight ChainRight Edge remains a fixed distance from
   right of Form
   XawChainTop ChainTop Edge remains a fixed distance from top of
   Form
   XawRubber Rubber Edges will move a proportional distance

Example

   If you wish to force the Form to never resize one or more of
   its children, then set left and right to XawChainLeft and top
   and bottom to XawChainTop. This will cause the child to remain
   a fixed distance from the top and left edges of the Form, and
   never to resize.

Convenience Routines

   To force or defer a re-layout of the Form, use
   void XawFormDoLayout( w,
                         do_layout);
   Widget w;
   Boolean do_layout;

   w
          Specifies the Form widget.

   do_layout
          Specifies whether the layout of the Form widget is
          enabled (True) or disabled (False).

   When making several changes to the children of a Form widget
   after the Form has been realized, it is a good idea to disable
   relayout until after all changes have been made.

Paned Widget




Application Header file <X11/Xaw/Paned.h>

Class Header file       <X11/Xaw/PanedP.h>

Class           panedWidgetClass

Class Name      Paned

Superclass      Constraint


   The Paned widget manages children in a vertically or
   horizontally tiled fashion. The panes may be dynamically
   resized by the user by using the grips that appear near the
   right or bottom edge of the border between two panes.

   The Paned widget may accept any widget class as a pane except
   Grip. Grip widgets have a special meaning for the Paned widget,
   and adding a Grip as its own pane will confuse the Paned
   widget.

Using the Paned Widget

   The grips allow the panes to be resized by the user. The
   semantics of how these panes resize is somewhat complicated,
   and warrants further explanation here. When the mouse pointer
   is positioned on a grip and pressed, an arrow is displayed that
   indicates the pane that is to be to be resized. While keeping
   the mouse button down, the user can move the grip up and down
   (or left and right). This, in turn, changes the size of the
   pane. The size of the Paned widget will not change. Instead, it
   chooses another pane (or panes) to resize. For more details on
   which pane it chooses to resize, see Layout Semantics.

   One pointer binding allows the border between two panes to be
   moved, without affecting any of the other panes. When this
   occurs the pointer will change to an arrow that points along
   the pane border.

   The default bindings for the Paned widget's grips are:
   Mouse button Pane to Resize - Vertical Pane to Resize -
   Horizontal
   1 (left) above the grip left of the grip
   2 (middle) adjust border adjust border
   3 (right) below the grip right of the grip
   _

Resources

   When creating a Paned widget instance, the following resources
   are retrieved from the argument list or the resource database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   betweenCursor Cursor Cursor A Depends on orientation
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   children ReadOnly WidgetList R NULL
   colormap Colormap Colormap   Parent's Colormap
   cursor Cursor Cursor   None
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   gripCursor Cursor Cursor A Depends on orientation
   gripIndent GripIndent Position   10
   gripTranslations Translations TranslationTable   see below
   height Height Dimension A Depends on orientation
   horizontalBetweenCursor Cursor Cursor   sb_up_arrow
   horizontalGripCursor Cursor Cursor   sb_h_double_arrow
   internalBorderColor BorderColor Pixel   XtDefaultForeground
   internalBorderWidth BorderWidth Dimension   1
   leftCursor Cursor Cursor   sb_left_arrow
   lowerCursor Cursor Cursor   sb_down_arrow
   mappedWhenManaged MappedWhenManaged Boolean   True
   numChildren ReadOnly Cardinal R 0
   orientation Orientation Orientation   XtorientVertical
   refigureMode Boolean Boolean   True
   rightCursor Cursor Cursor   sb_right_arrow
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   translations Translations TranslationTable   NULL
   upperCursor Cursor Cursor   sb_up_arrow
   verticalBetweenCursor Cursor Cursor   sb_left_arrow
   verticalGripCursor Cursor Cursor   sb_v_double_arrow
   width Width Dimension A Depends on orientation
   x Paned Position   0
   y Paned Position   0
   _

   cursor
          The cursor to use when the mouse pointer is over the
          Paned widget, but not in any of its children (children
          may also inherit this cursor). It should be noted that
          the internal borders are actually part of the Paned
          widget, not the children.

   gripCursor
          The cursor to use when the grips are not active. The
          default value is verticalGripCursor or
          horizontalGripCursor depending on the orientation of the
          Paned widget.

   gripIndent
          The amount of space left between the right (or bottom)
          edge of the Paned widget and all the grips.

   gripTranslation
          Translation table that will be applied to all grips.

   horizontalBetweenCursor

   verticalBetweenCursor
          The cursor to be used for the grip when changing the
          boundary between two panes. These resources allow the
          cursors to be different depending on the orientation of
          the Paned widget.

   horizontalGripCursor

   verticalGripCursor
          The cursor to be used for the grips when they are not
          active. These resources allow the cursors to be
          different depending on the orientation of the Paned
          widget.

   internalBorderColor
          A pixel value which indexes the widget's colormap to
          derive the internal border color of the widget's window.
          The class name of this resource allows
          Paned*BorderColor: blue to set the internal border color
          for the Paned widget. An optimization is invoked if
          internalBorderColor and background are the same, and the
          internal borders are not drawn. internalBorderWidth is
          still left between the panes, however.

   internalBorderWidth
          The width of the internal borders. This is the amount of
          space left between the panes. The class name of this
          resource allows Paned*BorderWidth: 3 to set the internal
          border width for the Paned widget.

   leftCursor

   rightCursor
          The cursor used to indicate which is the important pane
          to resize when the Paned widget is oriented
          horizontally.

   lowerCursor

   upperCursor
          The cursor used to indicate which is the important pane
          to resize when the Paned widget is oriented vertically.
          This is not the same as the number of panes, since this
          also contains a grip for some of the panes, use
          XawPanedGetNumSub to retrieve the number of panes.

   orientation
          The orientation to stack the panes. This value can be
          either XtorientVertical or XtorientHorizontal.

   refigureMode
          This resource allows pane layout to be suspended. If
          this value is False, then no layout actions will be
          taken. This may improve efficiency when adding or
          removing more than one pane from the Paned widget.

Constraint Resources

   Each child of the Paned widget may request special layout
   resources be applied to it. These constraint resources allow
   the Paned widget's children to specify individual layout
   requirements.

         Name              Class         Type    Notes  Default Value
      allowResize         Boolean       Boolean             False
          max               Max        Dimension          Infinity
          min               Min        Dimension       Height of Grips
   preferredPaneSize PreferredPaneSize Dimension          ask child
   resizeToPreferred      Boolean       Boolean             False
       showGrip          ShowGrip       Boolean             True
      skipAdjust          Boolean       Boolean             False
           _

   allowResize
          If this value is False the the Paned widget will
          disallow all geometry requests from this child.

   max

   min
          The absolute maximum or minimum size for this pane.
          These values will never be overridden by the Paned
          widget. This may cause some panes to be pushed off the
          bottom (or right) edge of the paned widget.

   preferredPaneSize
          Normally the paned widget makes a QueryGeometry call on
          a child to determine the preferred size of the child's
          pane. There are times when the application programmer or
          the user has a better idea of the preferred size of a
          pane. Setting this resource causes the value passed to
          be interpreted as the preferred size, in pixels, of this
          pane.

   resizeToPreferred
          Determines whether or not to resize each pane to its
          preferred size when the Paned widget is resized. See
          Layout Semantics for details.

   showGrip
          If True then a grip will be shown for this pane. The
          grip associated with a pane is either below or to the
          right of the pane. No grip is ever shown for the last
          pane.

   skipAdjust
          This resource is used to determine which pane is forced
          to be resized. Setting this value to True makes this
          pane less likely to be forced to be resized. See Layout
          Semantics for details.

Layout Semantics

   In order to make effective use of the Paned widget it is
   helpful to know the rules it uses to determine which child will
   be resized in any given situation. There are three rules used
   to determine which child is resized. While these rules are
   always the same, the panes that are searched can change
   depending upon what caused the relayout.

   Layout Rules

   1
          Do not let a pane grow larger than its max or smaller
          than its min.

   2
          Do not adjust panes with skipAdjust set.

   3
          Do not adjust panes away from their preferred size,
          although moving one closer to its preferred size is
          fine.

   When searching the children the Paned widget looks for panes
   that satisfy all the rules, and if unsuccessful then it
   eliminates rule 3 and then 2. Rule 1 is always enforced.

   If the relayout is due to a resize or change in management then
   the panes are searched from bottom to top. If the relayout is
   due to grip movement then they are searched from the grip
   selected in the direction opposite the pane selected.

Resizing Panes from a Grip Action

   The pane above the grip is resized by invoking the GripAction
   with UpLeftPane specified. The panes below the grip are each
   checked against all rules, then rules 2 and 1 and finally
   against rule 1 only. No pane above the chosen pane will ever be
   resized.

   The pane below the grip is resized by invoking the GripAction
   with LowRightPane specified. The panes above the grip are each
   checked in this case. No pane below the chosen pane will ever
   be resized.

   Invoking GripAction with ThisBorderOnly specified just moves
   the border between the panes. No other panes are ever resized.

Resizing Panes after the Paned widget is resized.

   When the Pane widget is resized it must determine a new size
   for each pane. There are two methods of doing this. The Paned
   widget can either give each pane its preferred size and then
   resize the panes to fit, or it can use the current sizes and
   then resize the panes to fit. The resizeToPreferred resource
   allows the application to tell the Paned widget whether to
   query the child about its preferred size (subject to the the
   preferredPaneSize) or to use the current size when refiguring
   the pane locations after the pane has been resized.

   There is one special case. All panes assume they should resize
   to their preferred size until the Paned widget becomes visible
   to the user.

Managing Children and Geometry Management

   The Paned widget always resizes its children to their preferred
   sizes when a new child is managed, or a geometry management
   request is honored. The Paned widget will first attempt to
   resize itself to contain its panes exactly. If this is not
   possible then it will hunt through the children, from bottom to
   top (right to left), for a pane to resize.

Special Considerations

   When a user resizes a pane with the grips, the Paned widget
   assumes that this new size is the preferred size of the pane.

Grip Translations

   The Paned widget has no action routines of its own, as all
   actions are handled through the grips. The grips are each
   assigned a default Translation table.



        <Btn1Down>:     GripAction(Start, UpLeftPane)

        <Btn2Down>:     GripAction(Start, ThisBorderOnly)
        <Btn3Down>:     GripAction(Start, LowRightPane)
        <Btn1Motion>:   GripAction(Move, UpLeftPane)
        <Btn2Motion>:   GripAction(Move, ThisBorderOnly)
        <Btn3Motion>:   GripAction(Move, LowRightPane)
        Any<BtnUp>:     GripAction(Commit)

   The Paned widget interprets the GripAction as taking two
   arguments. The first argument may be any of the following:

   Start
          Sets up the Paned widget for resizing and changes the
          cursor of the grip. The second argument determines which
          pane will be resized, and can take on any of the three
          values shown above.

   Move
          The internal borders are drawn over the current pane
          locations to animate where the borders would actually be
          placed if you were to move this border as shown. The
          second argument must match the second argument that was
          passed to the Start action, that began this process. If
          these arguments are not passed, the behavior is
          undefined.

   Commit
          This argument causes the Paned widget to commit the
          changes selected by the previously started action. The
          cursor is changed back to the grip's inactive cursor. No
          second argument is needed in this case.

Convenience Routines

   To enable or disable a child's request for pane resizing, use
   XawPanedAllowResize :
   void XawPanedAllowResize( w,
                             allow_resize);
   Widget w;
   Boolean allow_resize;

   w
          Specifies the child pane.

   allow_resize
          Specifies whether or not resizing requests for this
          child will be granted by the Paned widget.

   If allow_resize is True, the Paned widget allows geometry
   requests from the child to change the pane's height. If
   allow_resize is False, the Paned widget ignores geometry
   requests from the child to change the pane's height. The
   default state is True before the Pane is realized and False
   after it is realized. This procedure is equivalent to changing
   the allowResize constraint resource for the child.

   To change the minimum and maximum height settings for a pane,
   use XawPanedSetMinMax :
   void XawPanedSetMinMax( w,
                           max);
   Widget w;
   intmin, max;

   w
          Specifies the child pane.

   min
          Specifies the new minimum height of the child, expressed
          in pixels.

   max
          Specifies new maximum height of the child, expressed in
          pixels.

   This procedure is equivalent to setting the min and max
   constraint resources for the child.

   To retrieve the minimum and maximum height settings for a pane,
   use XawPanedGetMinMax :
   void XawPanedGetMinMax( w,
                           *max_return);
   Widget w;
   int*min_return, *max_return;

   w
          Specifies the child pane.

   min_return
          Returns the minimum height of the child, expressed in
          pixels.

   max_return
          Returns the maximum height of the child, expressed in
          pixels.

   This procedure is equivalent to getting the min and max
   resources for this child child.

   To enable or disable automatic recalculation of pane sizes and
   positions, use XawPanedSetRefigureMode :
   void XawPanedSetRefigureMode( w,
                                 mode);
   Widget w;
   Boolean mode;

   w
          Specifies the Paned widget.

   mode
          Specifies whether the layout of the Paned widget is
          enabled (True) or disabled (False).

   When making several changes to the children of a Paned widget
   after the Paned has been realized, it is a good idea to disable
   relayout until after all changes have been made.

   To retrieve the number of panes in a paned widget use
   XawPanedGetNumSub:
   int XawPanedGetNumSub( w);
   Widget w;

   w
          Specifies the Paned widget.

   This function returns the number of panes in the Paned widget.
   This is not the same as the number of children, since the grips
   are also children of the Paned widget.

Porthole Widget




Application Header file <X11/Xaw/Porthole.h>

Class Header file       <X11/Xaw/PortholeP.h>

Class           portholeWidgetClass

Class Name      Porthole

Superclass      Composite


   The Porthole widget provides geometry management of a list of
   arbitrary widgets, only one of which may be managed at any
   particular time. The managed child widget is reparented within
   the porthole and is moved around by the application (typically
   under the control of a Panner widget).

Resources

   When creating a Porthole widget instance, the following
   resources are retrieved from the argument list or from the
   resource database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   children ReadOnly WidgetList R NULL
   colormap Colormap Colormap   Parent's Colormap
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   height Height Dimension A see Layout Semantics
   mappedWhenManaged MappedWhenManaged Boolean   True
   numChildren ReadOnly Cardinal R 0
   reportCallback ReportCallback Callback   NULL
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   translations Translations TranslationTable   NULL
   width Width Dimension A see Layout Semantics
   x Position Position   0
   y Position Position   0
   _

   reportCallback
          A list of functions to invoke whenever the managed child
          widget changes size or position.

Layout Semantics

   The Porthole widget allows its managed child to request any
   size that is as large or larger than the Porthole itself and
   any location so long as the child still obscures all of the
   Porthole. This widget typically is used with a Panner widget.

Porthole Callbacks

   The functions registered on the reportCallback list are invoked
   whenever the managed child changes size or position:
   void ReportProc( porthole,
                    client_data,
                    report);
   Widget porthole;
   XtPointer client_data;
   XtPointer report;

   porthole
          Specifies the Porthole widget.

   client_data
          Specifies the client data.

   report
          Specifies a pointer to an XawPannerReport structure
          containing the location and size of the slider and the
          size of the canvas.

Tree Widget

Application Header file <X11/Xaw/Tree.h>
Class Header file       <X11/Xaw/TreeP.h>
Class           treeWidgetClass
Class Name      Tree
Superclass      Constraint

   The Tree widget provides geometry management of arbitrary
   widgets arranged in a directed, acyclic graph (i.e., a tree).
   The hierarchy is constructed by attaching a constraint resource
   called treeParent to each widget indicating which other node in
   the tree should be treated as the widget's superior. The
   structure of the tree is shown by laying out the nodes in the
   standard format for tree diagrams with lines drawn connecting
   each node with its children.

   The Tree sizes itself according to the needs of its children
   and is not intended to be resized by its parent. Instead, it
   should be placed inside another composite widget (such as the
   Porthole or Viewport) that can be used to scroll around in the
   tree.

Resources

   When creating a Tree widget instance, the following resources
   are retrieved from the argument list or from the resource
   database:
   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   ancestorSensitive AncestorSensitive Boolean D True
   autoReconfigure AutoReconfigure Boolean   False
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   children ReadOnly WidgetList R NULL
   colormap Colormap Colormap   Parent's Colormap
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   foreground Foreground Pixel   XtDefaultForeground
   gravity Gravity XtGravity   WestGravity
   height Height Dimension A see Layout Semantics
   hSpace HSpace Dimension   4
   lineWidth LineWidth Dimension   0
   mappedWhenManaged MappedWhenManaged Boolean   True
   numChildren ReadOnly Cardinal R 0
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   vSpace VSpace Dimension   4
   translations Translations TranslationTable   NULL
   width Width Dimension A see Layout Semantics
   x Position Position   0
   y Position Position   0

   autoReconfigure
          Whether or not to layout the tree every time a node is
          added or removed.

   gravity
          Specifies the side of the widget from which the tree
          should grow. Valid values include WestGravity,
          NorthGravity, EastGravity, and SouthGravity.

   hSpace

   vSpace
          The amount of space, in pixels, to leave between the
          children. This resource specifies the amount of space
          left between the outermost children and the edge of the
          box.

   lineWidth
          The width of the lines from nodes that do not have a
          treeGC constraint resource to their children.

Constraint Resources

   Each child of the Tree widget must specify its superior node in
   the tree. In addition, it may specify a GC to use when drawing
   a line between it and its inferior nodes.
      Name      Class     Type  Notes Default Value
     treeGC     TreeGC     GC             NULL
   treeParent TreeParent Widget           NULL

   treeGC
          This specifies the GC to use when drawing lines between
          this widget and its inferiors in the tree. If this
          resource is not specified, the Tree's foreground and
          lineWidth will be used.

   treeParent
          This specifies the superior node in the tree for this
          widget. The default is for the node to have no superior
          (and to therefore be at the top of the tree).

Layout Semantics

   Each time a child is managed or unmanaged, the Tree widget will
   attempt to reposition the remaining children to fix the shape
   of the tree if the resource is set. Children at the top (most
   superior) of the tree are drawn at the side specified by the
   resource.

   After positioning all children, the Tree widget attempts to
   shrink its own size to the minimum dimensions required for the
   layout.

Convenience Routines

   The most efficient way to layout a tree is to set
   autoReconfigure to False and then use the XawTreeForceLayout
   routine to arrange the children.
   void XawTreeForceLayout( w);
   Widget w;

   w
          Specifies the Tree widget.

Viewport Widget




Application Header file <X11/Xaw/Viewport.h>

Class Header file       <X11/Xaw/ViewportP.h>

Class           viewportWidgetClass

Class Name      Viewport

Superclass      Form


   The Viewport widget consists of a frame window, one or two
   Scrollbars, and an inner window. The size of the frame window
   is determined by the viewing size of the data that is to be
   displayed and the dimensions to which the Viewport is created.
   The inner window is the full size of the data that is to be
   displayed and is clipped by the frame window. The Viewport
   widget controls the scrolling of the data directly. No
   application callbacks are required for scrolling.

   When the geometry of the frame window is equal in size to the
   inner window, or when the data does not require scrolling, the
   Viewport widget automatically removes any scrollbars. The
   forceBars option causes the Viewport widget to display all
   scrollbars permanently.

Resources

   When creating a Viewport widget instance, the following
   resources are retrieved from the argument list or the resource
   database:

   Name Class Type Notes Default Value
   accelerators Accelerators AcceleratorTable   NULL
   allowHoriz Boolean Boolean   False
   allowVert Boolean Boolean   False
   ancestorSensitive AncestorSensitive Boolean D True
   background Background Pixel   XtDefaultBackground
   backgroundPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderColor BorderColor Pixel   XtDefaultForeground
   borderPixmap Pixmap Pixmap   XtUnspecifiedPixmap
   borderWidth BorderWidth Dimension   1
   children ReadOnly WidgetList R NULL
   colormap Colormap Colormap   Parent's Colormap
   depth Depth int C Parent's Depth
   destroyCallback Callback XtCallbackList   NULL
   forceBars Boolean Boolean   False
   height Height Dimension   height of the child
   mappedWhenManaged MappedWhenManaged Boolean   True
   numChildren ReadOnly Cardinal R 0
   reportCallback ReportCallback XtCallbackList   NULL
   screen Screen Screen R Parent's Screen
   sensitive Sensitive Boolean   True
   translations Translations TranslationTable   NULL
   useBottom Boolean Boolean   False
   useRight Boolean Boolean   False
   width Width Dimension   width of the child
   x Position Position   0
   y Position Position   0
   _

   allowHoriz

   allowVert
          If these resources are False then the Viewport will
          never create a scrollbar in this direction. If it is
          True then the scrollbar will only appear when it is
          needed, unless forceBars is True.

   forceBars
          When True the scrollbars that have been allowed will
          always be visible on the screen. If False the scrollbars
          will be visible only when the inner window is larger
          than the frame.

   reportCallback
          These callbacks will be executed whenever the Viewport
          adjusts the viewed area of the child. The call_data
          parameter is a pointer to an XawPannerReport structure.

   useBottom

   useRight
          By default the scrollbars appear on the left and top of
          the screen. These resources allow the vertical scrollbar
          to be placed on the right edge of the Viewport, and the
          horizontal scrollbar on the bottom edge of the Viewport.

Layout Semantics

   The Viewport widget manages a single child widget. When the
   size of the child is larger than the size of the Viewport, the
   user can interactively move the child within the Viewport by
   repositioning the scrollbars.

   The default size of the Viewport before it is realized is the
   width and/or height of the child. After it is realized, the
   Viewport will allow its child to grow vertically or
   horizontally if allowVert or allowHoriz are set, respectively.
   If the corresponding vertical or horizontal scrollbar is not
   enabled, the Viewport will propagate the geometry request to
   its own parent and the child will be allowed to change size
   only if the Viewport's parent allows it. Regardless of whether
   or not scrollbars are enabled in the corresponding direction,
   if the child requests a new size smaller than the Viewport
   size, the change will be allowed only if the parent of the
   Viewport allows the Viewport to shrink to the appropriate
   dimension.

   The scrollbar children of the Viewport are named horizontal and
   vertical. By using these names the programmer can specify
   resources for the individual scrollbars. XtSetValues can be
   used to modify the resources dynamically once the widget ID has
   been obtained with XtNameToWidget.

Note

   Although the Viewport is a Subclass of the Form, no resources
   for the Form may be supplied for any of the children of the
   Viewport. These constraints are managed internally and are not
   meant for public consumption.

Chapter 7. Creating New Widgets (Subclassing)

   Table of Contents

   Public Header File
   Private Header File
   Widget Source File

   Although the task of creating a new widget may at first appear
   a little daunting, there is a basic simple pattern that all
   widgets follow. The Athena Widget library contains a special
   widget called the Template widget that is intended to assist
   the novice widget programmer in writing a custom widget.

   Reasons for wishing to write a custom widget include:
     * Providing a graphical interface not currently supported by
       any existing widget set.
     * Convenient access to resource management procedures to
       obtain fonts, colors, etc., even if user customization is
       not desired.
     * Convenient access to user input dispatch and translation
       management procedures.
     * Access to callback mechanism for building higher-level
       application libraries.
     * Customizing the interface or behavior of an existing widget
       to suit a special application need.
     * Desire to allow user customization of resources such as
       fonts, colors, etc., or to allow convenient re-binding of
       keys and buttons to internal functions.
     * Converting a non-Toolkit application to use the Toolkit.

   In each of these cases, the operation needed to create a new
   widget is to "subclass" an existing one. If the desired
   semantics of the new widget are similar to an existing one,
   then the implementation of the existing widget should be
   examined to see how much work would be required to create a
   subclass that will then be able to share the existing class
   methods. Much time will be saved in writing the new widget if
   an existing widget class Expose, Resize and/or GeometryManager
   method can be used by the subclass.

   Note that some trivial uses of a ``bare-bones'' widget may be
   achieved by simply creating an instance of the Core widget. The
   class variable to use when creating a Core widget is
   widgetClass. The geometry of the Core widget is determined
   entirely by the parent widget.

   It is very often the case than an application will have a
   special need for a certain set of functions and that many
   copies of these functions will be needed. For example, when
   converting an older application to use the Toolkit, it may be
   desirable to have a "Window Widget" class that might have the
   following semantics:
     * Allocate 2 drawing colors in addition to a background
       color.
     * Allocate a text font.
     * Execute an application-supplied function to handle exposure
       events.
     * Execute an application-supplied function to handle user
       input events.

   It is obvious that a completely general-purpose
   WindowWidgetClass could be constructed that would export all
   class methods as callbacks lists, but such a widget would be
   very large and would have to choose some arbitrary number of
   resources such as colors to allocate. An application that used
   many instances of the general-purpose widget would therefore
   un-necessarily waste many resources.

   In this section, an outline will be given of the procedure to
   follow to construct a special-purpose widget to address the
   items listed above. The reader should refer to the appropriate
   sections of the X Toolkit Intrinsics - C Language Interface for
   complete details of the material outlined here. Section 1.4 of
   the Intrinsics should be read in conjunction with this section.

   All Athena widgets have three separate files associated with
   them:
     * A "public" header file containing declarations needed by
       applications programmers
     * A "private" header file containing additional declarations
       needed by the widget and any subclasses
     * A source code file containing the implementation of the
       widget

   This separation of functions into three files is suggested for
   all widgets, but nothing in the Toolkit actually requires this
   format. In particular, a private widget created for a single
   application may easily combine the "public" and "private"
   header files into a single file, or merge the contents into
   another application header file. Similarly, the widget
   implementation can be merged into other application code.

   In the following example, the public header file <
   X11/Xaw/Template.h >, the private header file <
   X11/Xaw/TemplateP.h > and the source code file <
   X11/Xaw/Template.c > will be modified to produce the
   "WindowWidget" described above. In each case, the files have
   been designed so that a global string replacement of "Template"
   and "template" with the name of your new widget, using the
   appropriate case, can be done.

Public Header File

   The public header file contains declarations that will be
   required by any application module that needs to refer to the
   widget; whether to create an instance of the class, to perform
   an XtSetValues operation, or to call a public routine
   implemented by the widget class.

   The contents of the Template public header file, <
   X11/Xaw/Template.h >, are:
..


/* Copyright (c) X Consortium 1987, 1988 */

#ifndef _Template_h
#define _Template_h

/****************************************************************
 *
 * Template widget
 *
 ****************************************************************/

/* Resources:

 Name   Class           RepType Default Value
 ----           -----           ------- -------------
 background     Background              Pixel   XtDefaultBackground
 border BorderColor             Pixel   XtDefaultForeground
 borderWidth    BorderWidth             Dimension       1
 destroyCallback        Callback                Pointer NULL
 height Height          Dimension       0
 mappedWhenManaged      MappedWhenManaged       Boolean True
 sensitive      Sensitive               Boolean True
 width  Width           Dimension       0
 x              Position                Position        0
 y              Position                Position        0

*/

/* define any special resource names here that are not in <X11/StringDef
s.h> */

#define XtNtemplateResource "templateResource"

#define XtCTemplateResource "TemplateResource"

/* declare specific TemplateWidget class and instance datatypes */

typedef struct _TemplateClassRec*       TemplateWidgetClass;
typedef struct _TemplateRec*    TemplateWidget;

/* declare the class constant */

extern WidgetClass templateWidgetClass;

#endif /* _Template_h */


   You will notice that most of this file is documentation. The
   crucial parts are the last 8 lines where macros for any private
   resource names and classes are defined and where the widget
   class datatypes and class record pointer are declared.

   For the "WindowWidget", we want 2 drawing colors, a callback
   list for user input and an exposeCallback callback list, and we
   will declare three convenience procedures, so we need to add



/* Resources:
        ...
 callback       Callback        Callback        NULL
 drawingColor1  Color   Pixel           XtDefaultForeground
 drawingColor2  Color   Pixel           XtDefaultForeground
 exposeCallback Callback        Callback        NULL
 font           Font    XFontStruct*    XtDefaultFont
        ...
 */

#define XtNdrawingColor1 "drawingColor1"
#define XtNdrawingColor2 "drawingColor2"
#define XtNexposeCallback "exposeCallback"

extern Pixel WindowColor1(\|/* Widget */\|);
extern Pixel WindowColor2(\|/* Widget */\|);
extern Font\ \ WindowFont(\|/* Widget */\|);


   Note that we have chosen to call the input callback list by the
   generic name, callback, rather than a specific name. If widgets
   that define a single user-input action all choose the same
   resource name then there is greater possibility for an
   application to switch between widgets of different types.

Private Header File

   The private header file contains the complete declaration of
   the class and instance structures for the widget and any
   additional private data that will be required by anticipated
   subclasses of the widget. Information in the private header
   file is normally hidden from the application and is designed to
   be accessed only through other public procedures; e.g.
   XtSetValues .

   The contents of the Template private header file, <
   X11/Xaw/TemplateP.h >, are:
/* Copyright (c) X Consortium 1987, 1988
 */

#ifndef _TemplateP_h
#define _TemplateP_h

#include <X11/Xaw/Template.h>
/* include superclass private header file */
#include <X11/CoreP.h>

/* define unique representation types not found in <X11/StringDefs.h> */

#define XtRTemplateResource "TemplateResource"

typedef struct {
        int empty;
} TemplateClassPart;

typedef struct _TemplateClassRec {
        CoreClassPart   core_class;
        TemplateClassPart       template_class;
} TemplateClassRec;

extern TemplateClassRec templateClassRec;

typedef struct {
        /* resources */
        char* resource;
        /* private state */
} TemplatePart;

typedef struct _TemplateRec {
        CorePart        core;
        TemplatePart    template;
} TemplateRec;

#endif /* _TemplateP_h */


   The private header file includes the private header file of its
   superclass, thereby exposing the entire internal structure of
   the widget. It may not always be advantageous to do this; your
   own project development style will dictate the appropriate
   level of detail to expose in each module.

   The "WindowWidget" needs to declare two fields in its instance
   structure to hold the drawing colors, a resource field for the
   font and a field for the expose and user input callback lists:
typedef struct {
        /* resources */
        Pixel color_1;
        Pixel color_2;
        XFontStruct* font;
        XtCallbackList expose_callback;
        XtCallbackList input_callback;
        /* private state */
        /* (none) */
} WindowPart;

Widget Source File

   The source code file implements the widget class itself. The
   unique part of this file is the declaration and initialization
   of the widget class record structure and the declaration of all
   resources and action routines added by the widget class.

   The contents of the Template implementation file, <
   X11/Xaw/Template.c >, are:
/* Copyright (c) X Consortium 1987, 1988
 */

#include <X11/IntrinsicP.h>
#include <X11/StringDefs.h>
#include "TemplateP.h"

static XtResource resources[] = {
#define offset(field) XtOffsetOf(TemplateRec, template.field)
        /* {name, class, type, size, offset, default_type, default_addr}
, */
    { XtNtemplateResource, XtCTemplateResource, XtRTemplateResource,
          sizeof(char*), offset(resource), XtRString, (XtPointer) "defau
lt" },
#undef offset
};

static void TemplateAction(/* Widget, XEvent*, String*, Cardinal* */);

static XtActionsRec actions[] =
{
        /* {name,       procedure}, */
        {"template",    TemplateAction},
};

static char translations[] =
"       <Key>:  template(\|) \\n\\
";

TemplateClassRec templateClassRec = {
  { /* core fields */
        /* superclass   */      (WidgetClass) &widgetClassRec,
        /* class_name   */      "Template",
        /* widget_size  */      sizeof(TemplateRec),
        /* class_initialize     */      NULL,
        /* class_part_initialize        */      NULL,
        /* class_inited */      FALSE,
        /* initialize   */      NULL,
        /* initialize_hook      */      NULL,
        /* realize      */      XtInheritRealize,
        /* actions      */      actions,
        /* num_actions  */      XtNumber(actions),
        /* resources    */      resources,
        /* num_resources        */      XtNumber(resources),
        /* xrm_class    */      NULLQUARK,
        /* compress_motion      */      TRUE,
        /* compress_exposure    */      TRUE,
        /* compress_enterleave */       TRUE,
        /* visible_interest     */      FALSE,
        /* destroy      */      NULL,
        /* resize       */      NULL,
        /* expose       */      NULL,
        /* set_values   */      NULL,
        /* set_values_hook      */      NULL,
        /* set_values_almost    */      XtInheritSetValuesAlmost,
        /* get_values_hook      */      NULL,
        /* accept_focus */      NULL,
        /* version      */      XtVersion,
        /* callback_private     */      NULL,
        /* tm_table     */      translations,
        /* query_geometry       */      XtInheritQueryGeometry,
        /* display_accelerator  */      XtInheritDisplayAccelerator,
        /* extension    */      NULL
  },
  { /* template fields */
        /* empty        */      0
  }
};

WidgetClass templateWidgetClass = (WidgetClass)&templateClassRec;

   The resource list for the "WindowWidget" might look like the
   following:
static XtResource resources[] = {
#define offset(field) XtOffsetOf(WindowWidgetRec, window.field)
        /* {name, class, type, size, offset, default_type, default_addr}
, */
        { XtNdrawingColor1, XtCColor, XtRPixel, sizeof(Pixel),
                  offset(color_1), XtRString, XtDefaultForeground },
        { XtNdrawingColor2, XtCColor, XtRPixel, sizeof(Pixel),
                  offset(color_2), XtRString, XtDefaultForeground },
        { XtNfont, XtCFont, XtRFontStruct, sizeof(XFontStruct*),
                  offset(font), XtRString, XtDefaultFont },
        { XtNexposeCallback, XtCCallback, XtRCallback, sizeof(XtCallback
List),
                  offset(expose_callback), XtRCallback, NULL },
        { XtNcallback, XtCCallback, XtRCallback, sizeof(XtCallbackList),
                  offset(input_callback), XtRCallback, NULL },
#undef offset
};

   The user input callback will be implemented by an action
   procedure which passes the event pointer as call_data. The
   action procedure is declared as:
/* ARGSUSED */
static void InputAction(w, event, params, num_params)
        Widget w;
        XEvent *event;
        String *params;         /* unused */
        Cardinal *num_params;   /* unused */
{
        XtCallCallbacks(w, XtNcallback, (XtPointer)event);
}

static XtActionsRec actions[] =
{
        /* {name,       procedure}, */
        {"input",       InputAction},
};

   and the default input binding will be to execute the input
   callbacks on KeyPress and ButtonPress :
static char translations[] =
"       <Key>:  input(\|) \\n\\
        <BtnDown>:      input(\|) \\
";

   In the class record declaration and initialization, the only
   field that is different from the Template is the expose
   procedure:
/* ARGSUSED */
static void Redisplay(w, event, region)
        Widget w;
        XEvent *event;  /* unused */
        Region region;
{
        XtCallCallbacks(w, XtNexposeCallback, (XtPointer)region);
}

WindowClassRec windowClassRec = {

        ...

        /* expose       */      Redisplay,

   The "WindowWidget" will also declare three public procedures to
   return the drawing colors and the font id, saving the
   application the effort of constructing an argument list for a
   call to XtGetValues :
Pixel WindowColor1(w)
        Widget w;
{
        return ((WindowWidget)w)->window.color_1;
}

Pixel WindowColor2(w)
        Widget w;
{
        return ((WindowWidget)w)->window.color_2;
}

Font WindowFont(w)
        Widget w;
{
        return ((WindowWidget)w)->window.font->fid;
}

   The "WindowWidget" is now complete. The application can
   retrieve the two drawing colors from the widget instance by
   calling either XtGetValues , or the WindowColor functions. The
   actual window created for the "WindowWidget" is available by
   calling the XtWindow function.

Chapter 8. Acknowledgments

   Many thanks go to Ralph Swick (Project Athena / Digital) who
   has contributed much time and effort to this widget set.
   Previous versions of the widget set are largely due to his time
   and effort. Many of the improvements that I have been able to
   make are because he provided a solid foundation to build upon.
   While much of the effort has been Ralph's, many other people
   have contributed to the code.
Mark Ackerman (formerly Project Athena)
Donna Converse (MIT X Consortium)
Jim Fulton (formerly MIT X Consortium)
Loretta Guarino-Reid (Digital WSL)
Charles Haynes (Digital WSL)
Rich Hyde (Digital WSL)
Mary Larson (Digital UEG)
Joel McCormack (Digital WSL)
Ron Newman (formerly Project Athena)
Jeanne Rich (Digital WSL)
Terry Weissman (formerly Digital WSL)

   While not much remains of the X10 toolkit, many of the ideas
   for this widget set come from that original version. The design
   and implementation of the X10 toolkit were done by:
Mike Gancarz (formerly Digital UEG)
Charles Haynes (Digital WSL)
Phil Karlton (formerly Digital WSL)
Kathleen Langone (Digital UEG)
Mary Larson (Digital UEG)
Ram Rao (Digital UEG)
Smokey Wallace (formerly Digital WSL)
Terry Weissman (formerly Digital WSL)

   I have used the formatting ideas, and some of the words from
   previous versions of this document. The X11R3 Athena widget
   document was written by:
Ralph R. Swick (Project Athena/ Digital)
Terry Weissman (formerly Digital WSL)
Al Mento (Digital UEG)

   Putting this manual together was a major task in and of itself.
   I would like to thank Ralph Swick, Donna Converse, and Jim
   Fulton for taking the time to help convert my technical
   knowledge into legible text. A special thanks to Jean Diaz
   (O'Reilly and Associates) for spending nearly a month with me
   working out all the annoying little details.
Chris D. Peterson
MIT X Consortium 1989

   The R5 edition of this document has been edited by the research
   staff of the MIT X Consortium, with significant contributions
   by Jim Fulton (NCD).
Donna Converse
MIT X Consortium 1991

   The R6 edition of this document has been edited to reflect
   changes brought about by research staff of the Omron
   Corporation, with special recognition to Li Yuhong, Seiji
   Kuwari, and Hiroshi Kuribayashi for the X11R5/contrib/lib/Xaw
   internationalization that inspired this version.
Frank Sheeran
Omron Corporation 1994
