<?xml version="1.0" encoding="utf-8"?>
<!-- http://blog.flexexamples.com/2008/05/20/changing-the-up-arrow-skin-and-down-arrow-skin-on-a-numericstepper-control-in-flex/ -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
        layout="vertical"
        verticalAlign="middle"
        backgroundColor="white">

    <mx:Script>
        <![CDATA[
            [Embed("assets/bullet_arrow_down.png")]
            private var downArrowIcon:Class;

            [Embed("assets/bullet_arrow_up.png")]
            private var upArrowIcon:Class;

            private function init():void {
                numericStepper.setStyle("downArrowSkin", downArrowIcon);
                numericStepper.setStyle("upArrowSkin", upArrowIcon);
            }
        ]]>
    </mx:Script>

    <mx:ApplicationControlBar dock="true">
        <mx:Button label="Click here to remove focus from NumericStepper control" />
    </mx:ApplicationControlBar>

    <mx:NumericStepper id="numericStepper" initialize="init();" />

</mx:Application>