If the mouse button is down, the mouseControlfunctionreturns the control(keyword) that was clicked, even if the
mouse has moved to another control(keyword).
If the mouse is over a graphic that is not selected, its interior is
considered to be within the graphic only if the graphic's filled
property is true. If the graphic'sfilled is false
and the graphic(keyword) is not selected, the mouseControlreturns the graphic's number only if the
mouse is over the graphic's border.