XtPopup(3Xt)        RISC/os Reference Manual         XtPopup(3Xt)



NAME
     XtPopup, XtCallbackNone, XtCallbackNonexclusive,
     XtCallbackExclusive, MenuPopup - map a pop-up

SYNTAX
     void XtPopup(popup_shell, grab_kind)
           Widget popup_shell;
           XtGrabKind grab_kind;

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

     void XtCallbackNonexclusive(w, client_data, call_data)
           Widget w;
           XtPointer client_data;
           XtPointer call_data;

     void XtCallbackExclusive(w, client_data, call_data)
           Widget w;
           XtPointer client_data;
           XtPointer call_data;

     void MenuPopup(shell_name)
           String shell_name;

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

     client_data
               Specifies the pop-up shell.

     grab_kind Specifies the way in which user events should be
               constrained.

     popup_shell
               Specifies the widget shell.

     w         Specifies the widget.

DESCRIPTION
     The XtPopup function performs the following:

     ⊕    Calls XtCheckSubclass to ensure popup_shell is a sub-
          class of Shell.

     ⊕    Generates an error if the shell's popped_up field is
          already True.

     ⊕    Calls the callback procedures on the shell's



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XtPopup(3Xt)        RISC/os Reference Manual         XtPopup(3Xt)



          popup_callback list.

     ⊕    Sets the shell popped_up field to True, the shell
          spring_loaded field to False, and the shell grab_kind
          field from grab_kind.

     ⊕    If the shell's create_popup_child field is non-NULL,
          XtPopup calls it with popup_shell as the parameter.

     ⊕    If grab_kind is either XtGrabNonexclusive or XtGrabEx-
          clusive, it calls:

     XtAddGrab(popup_shell, (grab_kind == XtGrabExclusive), False)

     ⊕    Calls XtRealizeWidget with popup_shell specified.

     ⊕    Calls XMapWindow with popup_shell specified.

     The XtCallbackNone, XtCallbackNonexclusive, and
     XtCallbackExclusive functions call XtPopup with the shell
     specified by the client data argument and grab_kind set as
     the name specifies.  XtCallbackNone, XtCallbackNonexclusive,
     and XtCallbackExclusive specify XtGrabNone, XtGrabNonex-
     clusive, and XtGrabExclusive, respectively.  Each function
     then sets the widget that executed the callback list to be
     insensitive by using XtSetSensitive.  Using these functions
     in callbacks is not required.  In particular, an application
     must provide customized code for callbacks that create pop-
     up shells dynamically or that must do more than desensitiz-
     ing the button.

     MenuPopup is known to the translation manager, which must
     perform special actions for spring-loaded pop-ups.  Calls to
     MenuPopup in a translation specification are mapped into
     calls to a nonexported action procedure, and the translation
     manager fills in parameters based on the event specified on
     the left-hand side of a translation.

     If MenuPopup is invoked on ButtonPress (possibly with modif-
     iers), the translation manager pops up the shell with
     grab_kind set to XtGrabExclusive and spring_loaded set to
     True.  If MenuPopup is invoked on EnterWindow (possibly with
     modifiers), the translation manager pops up the shell with
     grab_kind set to XtGrabNonexclusive and spring_loaded set to
     False.  Otherwise, the translation manager generates an
     error.  When the widget is popped up, the following actions
     occur:

     ⊕    Calls XtCheckSubclass to ensure popup_shell is a sub-
          class of Shell.

     ⊕    Generates an error if the shell's popped_up field is



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XtPopup(3Xt)        RISC/os Reference Manual         XtPopup(3Xt)



          already

          True.

     ⊕    Calls the callback procedures on the shell's
          popup_callback list.

     ⊕    Sets the shell popped_up field to True and the shell
          grab_kind and spring_loaded fields appropriately.

     ⊕    If the shell's create_popup_child field is non-NULL, it
          is called with popup_shell as the parameter.

     ⊕    Calls:

     XtAddGrab(popup_shell, (grab_kind == XtGrabExclusive), spring_loaded)

     ⊕    Calls XtRealizeWidget with popup_shell specified.

     ⊕    Calls XMapWindow with popup_shell specified.

     (Note that these actions are the same as those for XtPopup.)
     MenuPopup tries to find the shell by searching the widget
     tree starting at the parent of the widget in which it is
     invoked.  If it finds a shell with the specified name in the
     pop-up children of that parent, it pops up the shell with
     the appropriate parameters.  Otherwise, it moves up the
     parent chain as needed.  If MenuPopup gets to the applica-
     tion widget and cannot find a matching shell, it generates
     an error.

SEE ALSO
     XtCreatePopupShell(3Xt), XtPopdown(3Xt)
     X Toolkit Intrinsics - C Language Interface
     Xlib - C Language X Interface




















                         Printed 1/24/91  1 September 1988 Page 3