How to trigger a MouseEvent from TLF, my test doesn't work

  Hi,

      I run into a problem while using the Listener of TLF,

      Inside  the  TextFlow,  I have several Paragraphs.

      What I wish to accomplish is to trigger a mouse Event, like ROLL_OVER, ROLL_OUT event , when  my mouse is over a on one of the Paragraphs.

      I used to experiment a while , but never seem to work, just the examples below

      _textFlow.addEventListener(FlowElementMouseEvent.ROLL_OUT,onMouseHandler);

      _textFlow.addEventListener(FlowElementMouseEvent.ROLL_OVER,onMouseHandler);

       ///   which doesn't work.         i need the event response ,so i can manipulate the paragraph

private function onMouseHandler(e:FlowElementMouseEvent):void

{

     trace("onMouseHandler" +  e.type  );

     var para:ParagraphElement = e.flowElement.getParagraph();

     trace(para.textLength);

}  

Thanks  in   advance!!!