GUI.GetEventWidgetIDPart of GUI module

Syntax   GUI.GetEventWidgetID : int

Description   Returns the widget ID of the widget that was activated by the mouse button press or the keystroke. This function should only be called in an action procedure, as it will return 1 when there is no event that activated a widget being processed.

This function is used when a several buttons use the same action procedure to determine which button was pressed.

Example   The following program prints a message stating which button was selected.

        import GUI in "%oot/lib/GUI" 
        View.Set ("graphics:150;210") 
        var buttonNames : array 1 .. 5 of string := init ("Red", "Green",
            "Blue", "Yellow", "Purple")
        var buttons : array 1 .. 5 of int
        procedure ButtonPush
            for i : 1 .. 5
                if GUI.GetEventWidgetID = buttons (i) then
                    Text.Locate (1, 1)
                    put buttonNames (i), " selected"
                end if
            end for
        end ButtonPush
        for i : 1 .. 5
            buttons (i) := GUI.CreateButton (10, 210  40 * i, 110, 
                buttonNames (i), ButtonPush)
        end for
            exit when GUI.ProcessEvent
        end loop
Status   Exported qualified.

This means that you can only call the function by calling GUI.GetEventWidgetID, not by calling GetEventWidgetID.

See also   GUI.ProcessEvent.