How to properly use a UITabBarController in Monotouch

I understand what to do when using a UITabBarController with the MainWindow. But if when I'm in IB and I decide I want to have a UITabBarController, I only ever get a UIViewController that has a UITabBarController. If this is how it needs to be, then when do I .AddSubVi开发者_如何学Pythonew of the UITabBarController? In the ViewWillLoad of the UIViewController? Do I just change the class that is inherited from in the code?

Bit lost here.

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This is what I do:

• derive from UITabBarController in IB
• add the new class to my XIB
• (if I want to add new tabs outside of IB, I override LoadView in my tab bar controller class and do it in there)
• in AppDelegate.FinishedLaunching, I add my tab bar's view as a subview of 'window' (ie window.AddSubview(mainTabBar.View); )

Those steps work for me without any obvious problems.