title: Interstitial iAd within SKScene in iOS Sprite Kit
body: <p>The sample iAd code for interstitials uses the main ViewController to present the full-screen interstitial ad. </p>
  
  <p>However, I would like to be able to trigger the ad from the SKScene in my iOS Sprite Kit game.</p>
  
  <p>I can easily do so in the main view controller (<code>ViewController.m</code>) like so:</p>
  
  <pre><code>[self requestInterstitialAdPresentation];
  </code></pre>
  
  <p>However, I've tried to access the root view controller which sets up the scene in the <code>viewDidLoad</code> method of :</p>
  
  <pre><code>SKView * skView = (SKView *)self.view;
  SKScene * scene = [SKScene sceneWithSize:skView.bounds.size];
  [skView presentScene:scene];
  </code></pre>
  
  <p>In <code>SKScene.m</code> I've tried this:</p>
  
  <pre><code>[self.view.window.rootViewController requestInterstitialAdPresentation];
  </code></pre>
  
  <p>and X-Code throws this:</p>
  
  <pre><code>No visible @interface for 'UIViewController' declares the selector 'requestInterstitialAdPresentation'
  </code></pre>
  
  <p>This is probably something simple, basically I need to access the ViewController object that created the SKView and SKScene so I can send the <code>requestInterstitialAdPresentation</code> message to that object (and display the ad).</p>