Motif Widget Writer's Guide Migration Version

Motif 2.1 Widget Writer's Guide

ExmString

The String widget class

Format

#include <Exm/String.h>

DESCRIPTION

ExmString is a demonstration widget. OSF provides this widget solely to teach programmers how to write their own Motif widgets. OSF does not support this widget in any way.

The source code for the ExmString widget illustrates how to do the following:

Use the recommended resources for handling compound strings

Install the XmQTaccessTextual trait and define its trait methods

Calculate the baselines of each line of text in the compound string

ExmString is similar to the standard Motif toolkit widget XmLabel. The major difference between ExmString and XmLabel is that XmLabel can display either text or a pixmap, but ExmString can display only text.

ExmString is an instantiable widget and is also used as a superclass for other widgets, such as ExmCommandButton, ExmStringTransfer, and ExmMenuButton.

The ExmString widget receives enter and leave events, but it does not accept any button or key input.

The help callback is the only callback defined.

The text displayed by ExmString is a noneditable compound string. The ExmNcompoundString resource holds the value of this compound string. (See the Motif Programmer's Guide for more information on compound strings.) The text can be multilingual, multiline, and/or multifont. When an ExmString is insensitive, its text is stippled.

Unlike XmLabel, ExmString does not support accelerators or mnemonics.

ExmString forces the XmNtraversalOn resource to False.

Classes

ExmString inherits behavior and resources from Core, XmPrimitive, and ExmSimple.

The class pointer is exmStringWidgetClass.

The class name is ExmString.

New Resources

The following table defines a set of widget resources used by the programmer to specify data. The programmer can also set the resource values for the inherited classes to set attributes for this widget. To reference a resource by name or by class in a .Xdefaults file, remove the XmN, ExmN, XmC or ExmC prefix and use the remaining letters. To specify one of the defined values for a resource in a .Xdefaults file, remove the Xm or Exm prefix and use the remaining letters (in either lowercase or uppercase, but include any underscores between words). The codes in the "Access" column indicate if the given resource can be set at creation time (C), set by using XtSetValues (S), retrieved by using XtGetValues (G), or is not applicable (N/A).

ExmString Resource Set
Name	Class	Type	Default	Access
ExmNcompoundString	ExmCCompoundString	XmString	NULL	CSG
XmNalignment	XmCAlignment	unsigned char	XmALIGNMENT_CENTER	CSG
XmNrecomputeSize	XmCRecomputeSize	Boolean	True	CSG
XmNrenderTable	XmCRenderTable	XmRenderTable	dynamic	CSG

ExmNcompoundString

Specifies the text to be displayed.

XmNalignment

Specifies the alignment of the text:

XmALIGNMENT_BEGINNING (left alignment)

Causes the left sides of the lines of text to be aligned with the left edge of the widget window.

XmALIGNMENT_CENTER (center alignment)

Causes each line of text to be centered half way between the left and right edges of the widget window.

XmALIGNMENT_END (right alignment)

Causes the right sides of the lines of text to be aligned with the right edge of the widget window.

The preceding descriptions for text are correct when XmNstringDirection is XmSTRING_DIRECTION_L_TO_R. When that resource is XmSTRING_DIRECTION_R_TO_L, the descriptions for XmALIGNMENT_BEGINNING and XmALIGNMENT_END are switched.

XmNrecomputeSize

Specifies a Boolean value that indicates whether the widget attempts to resize to accommodate its contents as a result of an XtSetValues resource value that would change the size of the widget. If True, the widget attempts to shrink or expand to exactly fit the compound string. If False, the widget never attempts to change size on its own.

XmNrenderTable

Specifies the render table of the text used in the widget. If this value is NULL at initialization, the parent hierarchy of the widget is searched for an ancestor that holds the XmQTspecifyRenderTable trait. If such an ancestor is found, the font list is initialized to XmNbuttonRenderTable (for button subclasses) or XmNlabelRenderTable of the ancestor widget. If no such ancestor is found, the default is implementation dependent. Refer to XmRenderTable(3) for more information on the creation and structure of a font list.

Inherited Resources

ExmString inherits behavior and resources from the following superclasses. For a complete description of each resource, refer to the reference page for that superclass.

ExmSimple Resource Set
Name	Class	Type	Default	Access
ExmNsimpleShape	ExmCSimpleShape	unsigned char	ExmSHAPE_OVAL	CSG
XmNmarginHeight	XmCMarginHeight	Dimension	4	CSG
XmNmarginWidth	XmCMarginWidth	Dimension	4	CSG

XmPrimitive Resource Set
Name	Class	Type	Default	Access
XmNbottomShadowColor	XmCBottomShadowColor	Pixel	dynamic	CSG
XmNbottomShadowPixmap	XmCBottomShadowPixmap	Pixmap	XmUNSPECIFIED_PIXMAP	CSG
XmNconvertCallback	XmCCallback	XtCallbackList	NULL	C
XmNforeground	XmCForeground	Pixel	dynamic	CSG
XmNhelpCallback	XmCCallback	XtCallbackList	NULL	C
XmNhighlightColor	XmCHighlightColor	Pixel	dynamic	CSG
XmNhighlightOnEnter	XmCHighlightOnEnter	Boolean	False	CSG
XmNhighlightPixmap	XmCHighlightPixmap	Pixmap	dynamic	CSG
XmNhighlightThickness	XmCHighlightThickness	Dimension	2	CSG
XmNlayoutDirection	XmCLayoutDirection	XmDirection	dynamic	CG
XmNnavigationType	XmCNavigationType	XmNavigationType	XmNONE	CSG
XmNpopupHandlerCallback	XmCCallback	XtCallbackList	NULL	C
XmNshadowThickness	XmCShadowThickness	Dimension	2	CSG
XmNtopShadowColor	XmCTopShadowColor	Pixel	dynamic	CSG
XmNtopShadowPixmap	XmCTopShadowPixmap	Pixmap	dynamic	CSG
XmNtraversalOn	XmCTraversalOn	Boolean	False	CSG
XmNunitType	XmCUnitType	unsigned char	dynamic	CSG
XmNuserData	XmCUserData	XtPointer	NULL	CSG

Core Resource Set
Name	Class	Type	Default	Access
XmNaccelerators	XmCAccelerators	XtAccelerators	dynamic	CSG
XmNancestorSensitive	XmCSensitive	Boolean	dynamic	G
XmNbackground	XmCBackground	Pixel	dynamic	CSG
XmNbackgroundPixmap	XmCPixmap	Pixmap	XmUNSPECIFIED_PIXMAP	CSG
XmNborderColor	XmCBorderColor	Pixel	XtDefaultForeground	CSG
XmNborderPixmap	XmCPixmap	Pixmap	XmUNSPECIFIED_PIXMAP	CSG
XmNborderWidth	XmCBorderWidth	Dimension	0	CSG
XmNcolormap	XmCColormap	Colormap	dynamic	CG
XmNdepth	XmCDepth	int	dynamic	CG
XmNdestroyCallback	XmCCallback	XtCallbackList	NULL	C
XmNheight	XmCHeight	Dimension	dynamic	CSG
XmNinitialResourcesPersistent	XmCInitialResourcesPersistent	Boolean	True	C
XmNmappedWhenManaged	XmCMappedWhenManaged	Boolean	True	CSG
XmNscreen	XmCScreen	Screen *	dynamic	CG
XmNsensitive	XmCSensitive	Boolean	True	CSG
XmNtranslations	XmCTranslations	XtTranslations	dynamic	CSG
XmNwidth	XmCWidth	Dimension	dynamic	CSG
XmNx	XmCPosition	Position	0	CSG
XmNy	XmCPosition	Position	0	CSG

Translations

ExmString inherits all the translations of XmPrimitive. ExmString does not provide any additional translations beyond those defined by XmPrimitive.

Action Routines

ExmString provides no action routines of its own.

RELATED

Core(3), ExmCommandButton(3), ExmMenuButton(3), ExmSimple(3), and XmPrimitive(3).