Flex点击弹出图片窗口;

<?xml version="1.0" encoding="utf-8"?>? ? <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"? ? ?? ??? ??? ??? ??? ?layout="vertical"? ? ?? ??? ??? ??? ??? ?verticalAlign="middle"? ? ?? ??? ??? ??? ??? ?backgroundColor="white">? ? ?? ??? ? ?? ??? ?<mx:Style>? ? ?? ??? ??? ?global {? ? ?? ??? ??? ?modalTransparencyBlur: 0;? ? ?? ??? ??? ?modalTransparency: 0.9;? ? ?? ??? ??? ?modalTransparencyColor: black;? ? ?? ??? ??? ?modalTransparencyDuration: 500;? ? ?? ??? ??? ?}? ? ?? ??? ?</mx:Style>? ? ?? ??? ? ?? ??? ?<mx:Script>? ? ?? ??? ??? ?<![CDATA[? ? ?? ??? ??? ?import mx.controls.Image;? ? ?? ??? ??? ?import mx.managers.PopUpManager;? ? ?? ??? ??? ? ?? ??? ??? ?private const IMG_PREFIX:String = "http://www.helpexamples.com/flash/images/";? ? ?? ??? ??? ? ?? ??? ??? ?private function popIt(src:String):void {? ? ?? ??? ??? ?var img:Image = new Image();? ? ?? ??? ??? ?img.addEventListener(MouseEvent.CLICK,img_click);? ? ?? ??? ??? ?img.addEventListener(Event.COMPLETE,img_complete);? ? ?? ??? ??? ?img.load(IMG_PREFIX + src);? ? ?? ??? ??? ?img.toolTip = img.source.toString();? ? ?? ??? ??? ?PopUpManager.addPopUp(img,this,true);? ? ?? ??? ??? ?}? ? ?? ??? ??? ? ?? ??? ??? ?private function img_complete(evt:Event):void {? ? ?? ??? ??? ?var img:Image = evt.currentTarget as Image;? ? ?? ??? ??? ?img.width = img.contentWidth;? ? ?? ??? ??? ?img.height = img.contentHeight;? ? ?? ??? ??? ?PopUpManager.centerPopUp(img);? ? ?? ??? ??? ?}? ? ?? ??? ??? ? ?? ??? ??? ?private function img_click(evt:MouseEvent):void {? ? ?? ??? ??? ?var img:Image = evt.currentTarget as Image;? ? ?? ??? ??? ?PopUpManager.removePopUp(img);? ? ?? ??? ??? ?}? ? ?? ??? ??? ?]]>? ? ?? ??? ?</mx:Script>? ? ?? ??? ? ?? ??? ?<mx:ApplicationControlBar dock="true">? ? ?? ??? ??? ?<mx:Button label="image 1" click="popIt('image1.jpg');" />? ? ?? ??? ??? ?<mx:Button label="image 2" click="popIt('image2.jpg');" />? ? ?? ??? ??? ?<mx:Button label="image 3" click="popIt('image3.jpg');" />? ? ?? ??? ?</mx:ApplicationControlBar>? ? ?? ??? ? </mx:Application> ???