The HitTest  method returns the  graphics elements at a specific location or within a defined box. 
            Example
            The MouseDownDeleteRight function uses a mouse event function to define the mouse button action.
            FUNCTION MOUSEDOWNDELETERIGHT, Window, $
              X, Y, Button, KeyMods, Clicks
               
              PRINT, 'MouseDownHandler'
              HELP, Window, $
                 X, Y, Button, KeyMods, Clicks
               
              IF Button EQ 4 THEN BEGIN
                oVisList = Window.HitTest(X, Y)
                FOREACH vis, oVisList DO BEGIN
                  vis.Delete
                ENDFOREACH
                RETURN, 0 
              ENDIF ELSE  RETURN, 1 
               
            END
            The DeleteRight routine creates a graphic with text areas to test the MouseDownDeleteRight function.
            PRO DELETERIGHT
              
              p=plot(/test)
              t1=text(.5, .8, 'Text 1')
              t2=text(.5, .5, 'Text 2')
              p.window.MOUSE_DOWN_HANDLER='MouseDownDeleteRight'
               
              HELP, p, t1, t2
               
            END
            Syntax
            Result = graphic.HitTest(X, Y, [DIMENSIONS=dimensions])
            Return Value
            The HitTest method returns an array of graphics items at a specified location or within a box specified by dimensions. Use the returned references to manipulate the graphics.
            Arguments
            X
            The X location, in device coordinates, to use for the hit test.
            Y
            The Y location, in device coordinates, to use for the hit test.
            Keywords
            DIMENSIONS
            A two element vector [X,Y] containing the dimensions of a box centered on X, Y to use for the hit test.
            Version History
            
            See Also
            Select Method,
            Using IDL Graphics