Flex Toggle Button 开关按钮

?<?xml version="1.0" encoding="utf-8"?>
<mx:Button skin="{lockup}" toolTip="锁定"
?click="onClickBtn(event)" xmlns:mx="http://www.adobe.com/2006/mxml" toggle="true"
??? downSkin="{null}" upSkin="{null}" overSkin="{null}" focusSkin="{null}" >
?<mx:Script>
??<![CDATA[
???[Embed(source="assets/lockup.png")]
???private static var lockup:Class;
??
???[Embed(source="assets/lockdown.png")]
???private static var lockdown:Class;
???
??
???private function onClickBtn(event:MouseEvent):void{????
????if(this.selected)
????{
?????this.setStyle("skin", lockdown);
?????this.toolTip="解锁";
????}
????else
????{
?????this.setStyle("skin", lockup);
?????this.toolTip="锁定";
????}
???}
??]]>
?</mx:Script>
</mx:Button>