こんなで、 package { import flash.display.Sprite;import flash.utils.Timer;import flash.events.*; import flash.text.TextField; public class TimePanel extends Sprite { var myTimer:Timer,_t:TextField; public function TimePanel() { _t = new TextField();_t.text = "100";addChild(_t); myTimer= new Timer(1000); myTimer.addEventListener(flash.events.TimerEvent.TIMER , counter); setEvent(); } public function setEvent() { if (stage) { trace("画面に追加されてます"); stage.addEventListener(KeyboardEvent.KEY_UP, keyCheck); } else { trace("画面に追加されてません"); } } public function counter(e) { _t.text = String(Number(_t.text)-1); } public function keyCheck(e) { trace(e.keyCode);myTimer.start(); } } }