FLEX入门篇---------由Repeater创建的checkbox如何全选?

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="vertical">
	<mx:Script>
		<![CDATA[
			import mx.controls.CheckBox;
			[Bindable]
			private var rpAr:Array=[{id:0,name:"name1"},{id:1,name:"name2"}];
			
			private function selectAll():void{
				for(var i:uint=0;i<rpAr.length;i++){
					cb[i].selected=true;
				}
				
				//或者
				/*
				for(var i:uint=0;i<checkBox.length;i++){
					cb[i].selected=true;
				}
				*/
			}
		]]>
	</mx:Script>
	<mx:Label text="全选" click="selectAll();">
		
	</mx:Label>
	<mx:Tile width="100%" direction="vertical" borderStyle="inset" horizontalGap="10" verticalGap="15">
		<mx:Repeater id="rp" dataProvider="{rpAr}">
			<mx:CheckBox id="cb" label="{rp.currentItem.name}"/>
		</mx:Repeater>
	</mx:Tile>
</mx:Application>