[問題] as3的movie clip

[VV11 (任夭堂VVii)]

昨天在練習寫as3 (剛入門 囧)
在flash中寫的時候沒有問題
但寫在外部的時候就出錯了
請各位高手幫我解答一下  > 3<

以下是程式碼

package
{
        import flash.display.MovieClip;
        import flash.display.Sprite;
        import flash.events.Event;
        import flash.events.MouseEvent;
        import org.flashdevelop.utils.FlashConnect;

        public class test extends MovieClip {
                public function trace(str:*):void {
                        FlashConnect.trace(str.toString())
                }
                public function test() {
                        var empty:Sprite = new Sprite();
                        addChild(empty);
                        stage.addEventListener(MouseEvent.MOUSE_MOVE, mouseTest);
                        function mouseTest(e:MouseEvent):void {
                                var test_mc:MovieClip = new MovieClip();
                                test_mc.graphics.beginFill(0x000000);
                                test_mc.graphics.drawEllipse(0, 0, 20, 20);
                                test_mc.graphics.endFill();
                                test_mc.x = stage.mouseX;
                                test_mc.y = stage.mouseY;
                                test_mc.scaleX = test_mc.scaleY = 0.1;
                                test_mc.alpha = 0.1;
                                test_mc.cacheAsBitmap = true;
                                empty.addChild(test_mc);
                                trace(empty.numChildren);
                        }

                        root.addEventListener(Event.ENTER_FRAME, upMouse);
                        function upMouse(e:Event):void {

                                for (var i:int; i < empty.numChildren; i++) {
                                        var mc:MovieClip = empty.getChildAt(i);
                                        mc.scaleX = mc.scaleY += 0.2;
                                        if (mc.scaleX < 1.5) {
                                                mc.alpha += 0.1;
                                        }else {
                                                mc.alpha -= 0.1;
                                        }
                                        if (mc.alpha < 0) {
                                                empty.removeChild(mc);
                                        }
                                }
                        }
                }
        }
}

用fd輸出的時候會有錯誤訊息
test.as(38): col: 31 Error:
Implicit coercion of a value with static type flash.display:DisplayObject to
a possibly unrelated type flash.display:MovieClip.

改用displayObject就正常了

但是想加上瀘鏡卻沒有作用

可以麻煩幫我解答一下嗎~~謝謝 ><

--
→ kirbya:我不相信Son Vegas可以把臉上的痘痘Zoom大還很清楚!!
→ kirbya:         y
→ kirbya:          y
→ kirbya:            y
→ kirbya:           y
--
※ 發信站: 批踢踢實業坊(ptt.cc) 
◆ From: 122.116.92.103
→ cjcat2266:var mc:MovieClip = empty.getChildAt(i) as MovieClip;
→ cjcat2266:                                   type cast↑
→ VV11:喔喔喔  感謝cj大!