 <p>I don't see the problem immediately. A couple of things to consider:</p> <ul> <li>Add a constructor to B that calls super()</li> <li>You are adding the event listener to A, so A must be on the stage before the ENTER_FRAME event will occur</li> <li>You probably want to first use graphics.clear(), and then end with graphics.endFill()</li> </ul>