flip animation for right navigation bar button item

What is the best way to have the right navigation bar button flip like it does in the ipod when one changes from list view to sing开发者_如何学JAVAle song view? Subclass a custom view? Are there any api's out there that already do this?

thanks

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This question is similar, and discusses a few solutions. The main issue is that the UIBarButtonItem isn't a UIView, so you can't use the UIView transitions. iPhone flip right button (like iTunes)