title: Putting an ADBannerView on top of a UINavigationController
body: <p>I'm trying to put an iAd banner in an app that is based on a UINavigationController (it's not the standard nav-base app proposed by xcode, cause I don't need the table view).
  I'd like to place an ADBanner on its bottom, to be always visible, no matter how the user pops and pushes views.</p>
  
  <p>I studied the iAdSuite example in the apple sample code, but, though it's reported among the "best practices", I don't think it's the best practice for what I need. It basically declares an ADBannerView in the app delegate class and then implements the ADBannerViewDelegate methods for every single view the app needs. That means implementing the ADBannerViewDelegate methods over and over again on every view controller class you need! It doesn't seem too smart... :(</p>
  
  <p>I'd rather prefer to have an approach more similar to what Apple itself does in the tab bar based app, where you have a part of the window always occupied by the tab controller and all the views switching above without affecting the tab bar view below.
  You can't directly put an ADBannerView along with the nav controller in the app delegate, because ADBanner needs to be placed in a view controller (you get a runtime error otherwise).</p>
  
  <p>I tried to subclass from UIViewController, implementing the ADBannerViewDelegate in this class, and place it in the rootViewController along with a UINavigationController but I'm not having good luck with this approach...</p>
  
  <p>Has anybody found a good, simple way to to this? Any hint?</p>
  
  <p>Thank you for any help...</p>