Use NumericStepper to control the size of a Panel
<?xml version="1.0"?> <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute"> <mx:Panel id="panel" width="{panelWidth.value}" height="{panelHeight.value}"> <mx:NumericStepper id="panelWidth" value="200" minimum="200" maximum="400" stepSize="10" height="22"/> <mx:NumericStepper id="panelHeight" value="200" minimum="200" maximum="400" stepSize="10" height="22"/> </mx:Panel> </mx:Application>