gui_geteventwindow

#GUI.GetEventWindow

##Syntax GUI.GetEventWindow : int

##Description Returns the window ID of the window in which the event (mouse button or keystroke) took place. This function should only be called in an action procedure or in a default mouse or keystroke event handler, as it will return 1 when there is no event being processed.

This function is commonly used when several windows share the same layout. The same buttons in each window point to the same action procedures. To determine which button was actually pressed, the function is called to get the window.

##Example The following program creates four windows in a row, each with a button that, when pressed, causes a star to be drawn in that window.

    import GUI in "%oot/lib/GUI" 
    
    procedure DrawStar
        var windowID : int := GUI.GetEventWindow
        Window.Select (windowID)
        Draw.FillStar (25, 40, 175, 190, Rand.Int (10, 15))
    end DrawStar
    
    for i : 0 .. 3
        var window : int := Window.Open ("graphics:200;200") 
        % Place window above task bar, across from previous one.
        Window.SetPosition (window, 220 * i, 27) 
        var button : int := GUI.CreateButton (5, 5, 190, "Draw Star", 
            DrawStar) 
    end for
    
    loop
        exit when GUI.ProcessEvent
    end loop

##Status Exported qualified.

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

##See also gui_processevent.html.