title: How to implement a navigation controller in a subclass?
body: <p>Can anyone tell me about how to implement a navigation controller in a UIView subclass?
  I am creating four sub-classes, and I do not want the navigation control in first class, but I need to place it in the second, third and fourth subclass. How can I do that?</p>
  
  <p>Can anybody help me? How do I implement it?</p>