Dim out other components when UIPickerView is active

In my little iPhone application, I created UITableView with a UIPickerView which dynamically slides up when a cell is tapped. Since I don't want users to tap other cell when choosing value in the UIPickerView, I hope to make it less distractible by dimming out all the other components (the table, the title bar, etc). Kind of like what isolator does.

I think there might be some api method does开发者_开发技巧 this, but I can't find it. Any thoughts are greatly appreciated.

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When a cell is tapped you can add another uiview and set its alpha 0.5 and keep uipickerview above it so the background will look dimmed.

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If you have call back methods for presenting the picker, then you can disable and enable the user interaction of the root view of the view controller.