When you download some old code from the Interwebs with such like:
[self.window addSubview:self.viewController.view];
and it runs just fine... and later you update Xcode and start getting runtime errors:
Applications are expected to have a root view controller at the end of application launch
Fortunately the fix is easy:
[self.window setRootViewController:self.viewController];
Thanks, Interwebs!!
