How can I make an iPhone UIView "pulse" or fade from one color to another repeatedly?

I want a UIView with a glowing or pulsing开发者_运维技巧 effect, like the status bar during a call on the iPhone. Does anyone know how I would go about doing this? I've experimented with NSTimer but can't seem to find how to go about this.

Thanks!

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The animation API has the ability to message a callback you provide when the animation completes. You can use the API to daisy-chain together a series of animations from one state to another, giving the pulse effect you are looking for.