<?xml version="1.0" encoding="utf-8"?>
<!-- http://blog.flexexamples.com/2008/06/04/setting-the-tick-length-on-a-slider-control-in-flex/ -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
        layout="vertical"
        verticalAlign="middle"
        backgroundColor="white">

    <mx:Script>
        <![CDATA[
            import mx.events.SliderEvent;

            private function slider_change(evt:SliderEvent):void {
                slider.setStyle("tickLength", evt.value);
            }
        ]]>
    </mx:Script>

    <mx:HSlider id="slider"
            minimum="0"
            maximum="10"
            value="3"
            liveDragging="true"
            tickInterval="1"
            change="slider_change(event);" />

</mx:Application>