title: Call rootViewController to switch views within content view (iOS)
body: <p>I'm working on a pretty simple multiview app for the iOS and I've been following a great tutorial in an <a href="https://rads.stackoverflow.com/amzn/click/com/B004M8T01Q" rel="nofollow noreferrer" rel="nofollow noreferrer">Apress book</a>. I've basically got my rootViewController instantiated and displayed with the app delegate, and I've got a number of content viewControllers (6) which I'd like to swap in and out based on user input. However, in the book they perform their switches with a button on a toolbar placed in the rootView using Interface Builder. It fires a method in rootView that loads up the new content ViewController and displays it.</p>
  
  <p>My problem is that I'd like to perform the content view switch (that lies in my rootViewController instance), but I'd like to trigger the switch action with a button that's in my content view (and is therefore unavailable as my File Owner is my contentViewController, whose reference is held inside my rootViewController).</p>
  
  <p>Hopefully I've explained it well enough, please let me know if I should elaborate more. I appreciate any help!</p>