title: Clone or Copy UIViewController or UIView
body: <p>UII need copy, self controller or self.view, i have tried:</p>
  
  <pre><code>UIView* viewOfSelf =[self.view copy];
  UIViewController* controller = [self copy];
  
  UIView* viewOfSelf =[self.view mutableCopy];
  UIViewController* controller = [self mutableCopy];
  </code></pre>
  
  <p>The error is: </p>
  
  <pre><code>    -[UIViewController mutableCopyWithZone:]: unrecognized selector sent to instance 0xb803490
      -[UIView copyWithZone:]: unrecognized selector sent to instance 0x6e0acb0
  </code></pre>