hpux man page for xtcallbacka

XtCallbackNone()														  XtCallbackNone()

Name
  XtCallbackNone - callback function to pop up a widget.

Synopsis
  void XtCallbackNone(w, client_data, call_data)
	 Widget w;
	 XtPointer client_data;
	 XtPointer call_data;

Inputs
  w	    Specifies the widget.

  client_data
	    Specifies the popup shell.

  call_data Specifies the callback data, which is not used by this procedure.

Description
  XtCallbackNone()  calls  XtPopup() on the widget passed in the client_data argument with grab_mode set to XtGrabNone.  Then it calls XtSet-
  Sensitive() on w to make that widget insensitive.

  XtCallbackNone() is a convenience procedure designed to be registered on a widget's callback list (which is why  it  has  a  third,  unused
  argument).   The  widget  to	be  popped  up should be registered as client_data for the callback.  The reason that this callback makes its
  invoking widget insensitive is so that the user cannot request to popup the shell again while it is already up.

Usage
  To popup a shell with an exclusive grab or with no grab at all, you can use XtCallbackExclusive() or XtCallbackNone().  To popdown a	shell
  from a callback, use XtCallbackPopdown().

  Note that this function does not attempt to place the popup shell at any particular location, and for that reason may not be appropriate in
  many circumstances.

  It is also possible to pop up a shell with the XtMenuPopup action.

Example
  To arrange for the shell pshell to be popped up when the user clicks on the button widget button, you would use code like the following:

	 XtAddCallback(button,XtNcallback,XtCallbackNone,pshell);

  A companion example is presented on the XtCallbackPopdown() reference page.

See Also
  XtCallbackExclusive(1), XtCallbackNonexclusive(1), XtCallbackPopdown(1), XtMenuPopdown(1), XtMenuPopup(1), XtPopdown(1), XtPopup(1), XtSet-
  Sensitive(1).

Xt - Pop Ups															  XtCallbackNone()