Bind HBox backgroundColor to ColorPicker colorValue
<?xml version="1.0"?> <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"> <mx:Script> [Bindable] public var colorValue:int = 0x333999; public function changeHBoxStyle():void { colorValue = cp.selectedColor; } </mx:Script> <mx:HBox width="100" height="100" backgroundColor="{colorValue}" /> <mx:ColorPicker id="cp" showTextField="true" change="changeHBoxStyle()" selectedColor="0x333999" /> </mx:Application>