Display message like the mute/volume transparent rectangle on iPhone SDK

Does anyone know how to use the semi-transparent rectangle to display info to the user on the iPhone SDK? I mean the one that is used when you mute the phone or press the volume up/down keys开发者_如何学编程.

Thanks a lot.

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There are many drop in classes out there for you to choose from.

MBProgressHUD

Also, check out TapkuLibrary also has a nice progress hud class.