Rotate after Button creation completed
<?xml version="1.0" encoding="utf-8"?> <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="vertical"> <mx:Button id="button2" label="My Button With Customized Effect" > <mx:creationCompleteEffect> <mx:Rotate angleFrom="45" angleTo="0" duration="1000" /> </mx:creationCompleteEffect> </mx:Button> </mx:Application>