DataGrid 여러 컬럼에서 같은 itemrenderer 사용하기

<?xml version=”1.0″ encoding=”utf-8″?>
<mx:Canvas xmlns:mx=”http://www.adobe.com/2006/mxml” width=”182″ height=”30″ implements=”mx.controls.listClasses.IDropInListItemRenderer” horizontalScrollPolicy=”off”>
<mx:Script>
<![CDATA[
import mx.controls.listClasses.BaseListData;
import mx.controls.dataGridClasses.DataGridListData;
protected var _listData:DataGridListData;
override public function set data(value:Object):void
{
setIt(value);
}
public function get listData():BaseListData
{
return _listData;
}
public function set listData(value:BaseListData):void
{
_listData = DataGridListData(value);
invalidateProperties();
}
private function setIt(value:Object):void
{
if(value && _listData)
{
if(_listData.columnIndex == 0)
{
img.source="a.gif"
}
else if(_listData.columnIndex == 1)
{
img.source="b.gif"
}
else
{
img.source="c.gif"
}
}
}

]]>
</mx:Script>
<mx:Image x=”10″ y=”6″ width=”20″ height=”20″ id=”img”/>
</mx:Canvas>