XmStringComponentType

Motif 2.1 Programmer's Reference

XmStringComponentType

Data type for compound string components

Format

#include <Xm/Xm.h>

DESCRIPTION

XmStringComponentType is the data type specifying compound string component types. A compound string component identifies some part of a compound string, and can have a value and length. A compound string component can be one of the following types. These component types are grouped according to their length and value types.

The following components have values of NULL and lengths of 0 (zero).

XmSTRING_COMPONENT_SEPARATOR

This component usually maps to a newline or carriage return in displayed text.

XmSTRING_COMPONENT_TAB

This component may be thought of as a text component containing only a single tab.

XmSTRING_COMPONENT_LAYOUT_POP

The layout direction is kept on a stack, with the current direction kept on top of the stack. When this component is read, the most recently read layout direction is popped off the stack and replaced by the direction immediately before it.

XmSTRING_COMPONENT_END

This component marks the end of a compound string. No other components should follow. If an application does not place an XmSTRING_COMPONENT_END component at the end of an XmString, Motif automatically does it for the application.

The following component has a value of XmDirection and the length of that direction.

XmSTRING_COMPONENT_LAYOUT_PUSH

The layout direction is kept on a stack, with the current direction kept on top of the stack. This component replaces the current layout direction, and causes another to be pushed onto the top of this stack.

The following component has a value of XmStringDirection and the length of that direction.

XmSTRING_COMPONENT_DIRECTION

This component sets the string direction by overriding the previous string direction.

The following components have values of type char * or some equivalent type, and the lengths of these types.

XmSTRING_COMPONENT_LOCALE_TEXT

This component contains the multibyte text of a compound string.

XmSTRING_COMPONENT_WIDECHAR_TEXT

This component contains the widechar text of a compound string.

XmSTRING_COMPONENT_TEXT

This component contains the charset text of a compound string. Note that a compound string cannot contain both charset and locale (multibyte or widechar) text.

XmSTRING_COMPONENT_RENDITION_BEGIN

This component marks the beginning of a new rendition. All text following this component will be rendered using this rendition as the primary one. If there is already a rendition in effect, it is kept in memory and used to fill in any unspecified values in the primary rendition. Renditions are kept until a corresponding XmSTRING_COMPONENT_RENDITION_END component is encountered.

XmSTRING_COMPONENT_RENDITION_END

This component signifies that the specified rendition will no longer be used to render text, and will not be available to fill in unspecified values of newer renditions.

XmSTRING_COMPONENT_UNKNOWN

This component type signifies that the component contents belong to an unknown component type.

XmSTRING_COMPONENT_LOCALE

Use this component to specify the locale in which an internationalized application is to execute. The only valid character string for this component is _MOTIF_DEFAULT_LOCALE.

XmSTRING_COMPONENT_TAG

For charset text, this is the tag of the font to be used to display the text. This tag is sometimes referred to as the charset tag or the fontlist tag.

XmSTRING_COMPONENT_CHARSET

This component is obsolete and remains for compatibility with previous releases. It has been replaced by XmSTRING_COMPONENT_TAG.

XmSTRING_COMPONENT_FONTLIST_ELEMENT_TAG

This component is obsolete and remains for compatibility with previous releases. It has been replaced by XmSTRING_COMPONENT_TAG.

Some compound string components depend on values defined in other components. The XmSTRING_COMPONENT_TAB component definition, for example, depends on information in the XmSTRING_COMPONENT_RENDITION_BEGIN. To account for these dependencies, a typical compound string will have its member components in the following order:

[
  [ XmSTRING_COMPONENT_LAYOUT_PUSH ]
  [ XmSTRING_COMPONENT_RENDITION_BEGIN ]*
  [ XmSTRING_COMPONENT_TAG | XmSTRING_COMPONENT_LOCALE ]
  [ XmSTRING_COMPONENT_TAB ]*
  [ XmSTRING_COMPONENT_DIRECTION ]
  [ XmSTRING_COMPONENT_TEXT |
    XmSTRING_COMPONENT_LOCALE_TEXT |
    XmSTRING_COMPONENT_WIDECHAR_TEXT ]
  [ XmSTRING_COMPONENT_RENDITION_END ]*
  [ XmSTRING_COMPONENT_LAYOUT_POP ]
  [ XmSTRING_COMPONENT_SEPARATOR ]
]*
XmSTRING_COMPONENT_END