Application style sets background image to be empty
<?xml version="1.0"?> <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"> <mx:Style> @namespace mx "http://www.adobe.com/2006/mxml"; mx|Application { backgroundImage: ""; } </mx:Style> <mx:Button id="myButton" styleName="myFontStyle" label="Click Here"/> </mx:Application>