Flex中如何通过addChild()函数在List中显示一个Sprite的例子

转载的代码，本人也是刚刚入门，所以添加不上解释，望有高手可以添加一下注释以供学习。

<?xml
version="1.0"
encoding="utf-8"?>

<s:Application name="Spark_SpriteVisualElement_addChild_test"

xmlns:fx="http://ns.adobe.com/mxml/2009"

xmlns:s="library://ns.adobe.com/flex/spark"

xmlns:mx="library://ns.adobe.com/flex/halo"

initialize="init();">

<fx:Script>

<![CDATA[

private const spr1:Sprite = new Sprite();

private const spr2:Sprite = new Sprite();

private function init():void {

spr1.graphics.beginFill(0xFF0000, 0.5);

spr1.graphics.drawRect(10, 10, 100, 80);

spr1.graphics.endFill();
con.addChild(spr1);

spr2.graphics.beginFill(0x0000FF, 0.3);

spr2.graphics.drawRect(20, 20, 80, 100);

spr2.graphics.endFill();
con.addChild(spr2);
}
]]>
</fx:Script>

<s:SpriteVisualElement id="con"
/>

</s:Application>