Setting alternating item colors on a Flex PopUpButton control

<?xml version="1.0"?> <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="horizontal" verticalAlign="top" backgroundColor="white"> <mx:Script> <![CDATA[ import mx.controls.Menu; [Bindable] private var menu:Menu; private function initMenu():void { menu = new Menu(); menu.dataProvider = arr; } ]]> </mx:Script> <mx:Array id="arr"> <mx:Object label="Button" /> <mx:Object label="ButtonBar" /> <mx:Object label="ColorPicker" /> <mx:Object label="ComboBox" /> </mx:Array> <mx:Style> PopUpButton { popUpStyleName: myCustomPopUpStyleName; } .myCustomPopUpStyleName { fontWeight: normal; textAlign: left; alternatingItemColors: white, #EEEEEE; } </mx:Style> <mx:PopUpButton id="popUpButton" label="Select a control..." popUp="{menu}" preinitialize="initMenu();" creationComplete="popUpButton.open();" /> </mx:Application>