Interface Builder won't allow me to select a nib name for tab bar

I just upgraded to xCode 4 and I am having so much trouble setting the nib name for a particular ta开发者_StackOverflow中文版b. If I choose nib name it drops down a list with nothing, if I just type in the nib name I want, when I run it, it does not show that view. And I have specified the class for that tab. I have a tab bar and a navigation controller set to one of the tabs.

Thanks

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You can add an uinavigationcontroller to your uitabbarcontroller.

Now you can add an uiviewcontroller to the added uinavigationcontroller.

Now you can change the class of the last added uiviewcontroller, and set the nib-name for this item.