get_help
for accesing help files written in HTML and
accessible in the libhelp
search path. This procedure can be directly called or be used as
a callback procedure for Xt toolkit callbacks (can be casted to
XtCallbackProc
).
#include <help.h> void get_help (Widget parent, XtPointer call_data, XtPointer client_data);
After the Xt toolkit is initialized, the application calls
get_help
as needed.
Widget parent
- arbitrary managed or realized widget, for example the toplevel shell. It is used to determine the display. If called as callback it is the Widget for which help is requested.
XtPointer call_data
'\0'
terminated string holdind the URL for the helpfile.XtPointer client_data
- is not used.
For example, you can have a help-pushbutton (Widget
help_button
). To use the help-file "app-help.html" when the
pushbutton is presses you would write (if you are using C):
XtAddCallback (help_button, XmNactivateCallback, (XtCallbackProc) get_help, (XtPointer) "app-help.html");
Of course, there are some limitations on libhelp URLs (Uniform Resource Locators).