Importance of rootViewController


Having trouble understanding why setting a root view controller is so important. The code given on p. 149-150 for setRootViewController doesn’t seem that exciting but there’s mention that “this method does a few more things”. Can someone expand on those “few more things” and why this property is so important in iOS 5? Thanks.


It’s an iOS 4 method, and it’s side effects are that it removes all over views from the window and it resizes the view of the root view controller to fit the window.