;  class Foo {      private var tl:MovieClip; // timeline     private var mc:MovieClip; // the attached movieclip      function Foo(t:MovieClip){         tl = t;         mc = tl.attachMovie("AttachMe", "mc", 00);         var b:Button = mc.btn;         b.addEventListener("click", Delegate.create(this, onClick));     }     private function onClick(e:Object):Void