Volume 6A: Motif Programming Manual

to hang, so we don't recommend using it unless you are using Motif 1.2.

You may have noticed that the PopupMenu shown in the figure has accelerators associated with it. These accelerators

only take effect if the input focus is in the widget that contains the menu.

The only time you should ever add an event handler to pop up a menu is when you are using a PopupMenu. You

should not attach PulldownMenus or OptionMenus to arbitrary Motif widgets. It is also inappropriate to use a

PopupMenu on a CascadeButton, since it already has a menu associated with it.

16.4.4 Building Option Menus

In this final section on generalized menu creation methods, we examine how to create OptionMenus using the

BuildMenu() function. In this case, the underlying function is XmCreateOptionMenu(), which is another

convenience routine provided by the Motif toolkit. The routine creates a RowColumn widget that manages the Label

and CascadeButton widgets that define the OptionMenu, but we must create the actual PulldownMenu ourselves. The

final version of the BuildMenu() function is shown in the source code

/* build_option.c −− The final version of BuildMenu() is used to

* build popup, option, pulldown −and− pullright menus. Menus are

* defined by declaring an array of MenuItem structures as usual.

*/

#include <Xm/MainW.h>

#include <Xm/ScrolledW.h>

#include <Xm/PanedW.h>

#include <Xm/RowColumn.h>

#include <Xm/DrawingA.h>

#include <Xm/CascadeBG.h>

#include <Xm/ToggleB.h>

#include <Xm/ToggleBG.h>

#include <Xm/PushB.h>