title: Adcolony unable to find the currently visible UIViewController
body: <p>I was integrating the adcolony video ads in my iphone game. When displaying the ad we are getting the error </p>
  
  <p>" ADCOLONY 2.0.1 [<strong>* ERROR *</strong>] AdColony has ads, but could not display them. AdColony was unable to find the currently visible UIViewController for your app. Please ensure that your key UIWindow has a rootViewController."</p>
  
  <p>When i checked the code in appdelegate we had already set the rootviewcontroller of UIWindow like this :</p>
  
  <p><code>self.viewController_ipad = [[ViewController_ipad alloc] initWithNibName:nil bundle:nil] ;
          window.rootViewController = self.viewController_ipad;
          [window makeKeyAndVisible];</code></p>
  
  <p>Still i am getting this error. Please guide us in right direction to solve this problem ?</p>
  
  <p>Thanks in advance!</p>