UIPopover locking background view

I am trying to replicate the iPad passcode view. Which basically is a popover with no arrow direction, that locks the background view kinda like a modal view controller.

My question: Is there a way to lock the underlying background view when presenting a popover.

My idea: The only real solution that i could co开发者_如何学Cme up with is placing that popover inside a modal view controller. and presenting it that way.

Thoughts?

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Use the modalInPopover property of your view controller: http://developer.apple.com/iphone/library/documentation/uikit/reference/UIViewController_Class/Reference/Reference.html#//apple_ref/doc/uid/TP40006926-CH3-SW72

This question provides some information on making a popover with no arrows, though it's not clear whether it's correct or not: UIPopover without any arrows