title: Re assigning window root view controller
body: <p>In my one of the applications I needed to re assign rootview controller,so for that I have done like below,</p>
  
  <pre><code>   self.wndow.rootViewController = nil;
     self.window.rootVIewController = navigationController;
  </code></pre>
  
  <p>But now the problem is previously used class objects are not releasing from memory,retain count of living objects goes on increasing while I re assigning new window rootVIewController, and dealloc method of that Class is not called, I checked retain counts with xcode profile instruments..,any one can help me on this?</p>