Set scale grid for VBox
<?xml version="1.0" encoding="utf-8"?> <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"> <mx:Style> @namespace mx "http://www.adobe.com/2006/mxml"; mx|VBox { backgroundImage: Embed("a.png",scaleGridTop="5", scaleGridLeft="5", scaleGridBottom="29", scaleGridRight="29"); backgroundSize: "100%"; } </mx:Style> <mx:VBox height="200" width="200" /> </mx:Application>