UISlider Available Value

I would like to know how to reproduce the UISlider appearance of streaming audio/video in the native iPhone player. 开发者_JAVA技巧I have it figured out except how to reproduce the available section and the empty part for the section not available.

alt text http://dl.dropbox.com/u/1407026/Screen%20shot%202010-01-14%20at%2011.16.10%20PM.png

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You may end up discovering that that control isn't a UISlider as you know it. It could be a subclass or a completely different control that simply resembles a UISider.

I don't know this as a 100% true fact, but I say it because this control and the UISlider control both behave quite differently and have slightly different appearances.