title: Display UIImageView in full screen (320*480)
body: <p>I know there are some questions about UIImageView full-size have been asked but I'm still stuck with my problems.</p>
  
  <p>I have a navigation bar, a scrollview, a UIImageView (named avatarTest) and a button. When I press the image, the UIImageView expand to full-size (320*480) and set the avatarTest.contentMode is ModeCenter. </p>
  
  <p>My problems are:</p>
  
  <ul>
  <li><p>UIImageView expanded to 320*480 but it didn't replace the navigation bar and status bar (like picture 1 and 2)</p></li>
  <li><p>When I scroll down (now my button appear) and I press image, the UIImageView still expand according the old view. I want it expand to the full size, fill my current view (window) (like picture 3 and 4)</p></li>
  <li><p>I want to know how to determine the origin frame (CGRectMake) of UIImageView by code so I can code for the 2nd press action (resize the image to origin)</p></li>
  </ul>
  
  <p><img src="https://i.stack.imgur.com/ulTLU.png" alt="enter image description here"></p>
  
  <p><img src="https://i.stack.imgur.com/ueKyE.png" alt="enter image description here"></p>
  
  <p><img src="https://i.stack.imgur.com/vWbqJ.png" alt="enter image description here"></p>
  
  <p><img src="https://i.stack.imgur.com/0hprQ.png" alt="enter image description here"></p>
  
  <p>Here are some my viewController.m codes:</p>
  
  <pre><code>- (IBAction) expand {
  
      [UIView animateWithDuration:0.5f animations:^{
      CGRect screenRect = [[UIScreen mainScreen] bounds];
          CGFloat screenWidth = screenRect.size.width;
          CGFloat screenHeight = screenRect.size.height;            
          avatarTest.frame=CGRectMake(self.view.frame.origin.x, self.view.frame.origin.y, screenWidth, screenHeight);
          avatarTest.contentMode=UIViewContentModeCenter;
          avatarTest.backgroundColor = [UIColor blackColor];
  
  
      }]; 
  } 
  </code></pre>