The following example shows how you can set the border color on a Flex ProgressBar control by setting the borderColor style.
Full code after the jump.
<?xml version="1.0" encoding="utf-8"?>
<!-- http://blog.flexexamples.com/2008/03/27/setting-the-border-color-on-a-progressbar-control-in-flex/ -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
layout="vertical"
verticalAlign="middle"
backgroundColor="white">
<mx:ApplicationControlBar dock="true">
<mx:Form styleName="plain">
<mx:FormItem label="borderColor:">
<mx:ColorPicker id="colorPicker" />
</mx:FormItem>
</mx:Form>
</mx:ApplicationControlBar>
<mx:ProgressBar id="progressBar"
mode="manual"
labelPlacement="center"
borderColor="{colorPicker.selectedColor}"
height="50"
creationComplete="progressBar.setProgress(76, 100);" />
</mx:Application>
View source is enabled in the following example.





impressive!