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XtAddGrab(3Xt)



XtAddGrab(3Xt)                                     XtAddGrab(3Xt)



NAME
     XtAddGrab, XtRemoveGrab - redirect user input to a modal
     widget

SYNTAX
     void XtAddGrab(w, exclusive, spring_loaded)
           Widget w;
           Boolean exclusive;
           Boolean spring_loaded;

     void XtRemoveGrab(w)
           Widget w;

ARGUMENTS
     exclusive Specifies whether user events should be dispatched
               exclusively to this widget or also to previous
               widgets in the cascade.

     spring_loaded
               Specifies whether this widget was popped up
               because the user pressed a pointer button.

     w         Specifies the widget to add to or remove from the
               modal cascade.

DESCRIPTION
     The XtAddGrab function appends the widget (and associated
     parameters) to the modal cascade and checks that exclusive
     is True if spring_loaded is True.  If these are not True,
     XtAddGrab generates an error.

     The modal cascade is used by XtDispatchEvent when it tries
     to dispatch a user event.  When at least one modal widget is
     in the widget cascade, XtDispatchEvent first determines if
     the event should be delivered.  It starts at the most recent
     cascade entry and follows the cascade up to and including
     the most recent cascade entry added with the exclusive
     parameter True.

     This subset of the modal cascade along with all descendants
     of these widgets comprise the active subset.  User events
     that occur outside the widgets in this subset are ignored or
     remapped.  Modal menus with submenus generally add a submenu
     widget to the cascade with exclusive False.  Modal dialog
     boxes that need to restrict user input to the most deeply
     nested dialog box add a subdialog widget to the cascade with
     exclusive True.  User events that occur within the active
     subset are delivered to the appropriate widget, which is
     usually a child or further descendant of the modal widget.

     Regardless of where on the screen they occur, remap events
     are always delivered to the most recent widget in the active



XWIN 3.0               Last change: 9/1/88                 .ie t





XtAddGrab(3Xt)                                     XtAddGrab(3Xt)



     subset of the cascade that has spring_loaded True, if any
     such widget exists.

     The XtRemoveGrab function removes widgets from the modal
     cascade starting at the most recent widget up to and includ-
     ing the specified widget.  It issues an error if the speci-
     fied widget is not on the modal cascade.

SEE ALSO
     X Toolkit Intrinsics - C Language Interface
     Xlib - C Language X Interface












































XWIN 3.0               Last change: 9/1/88                 .ie t





XtAddGrab(3Xt)                                     XtAddGrab(3Xt)























































XWIN 3.0               Last change: 9/1/88                 .ie t






Typewritten Software • bear@typewritten.org • Edmonds, WA 98026