title: Resize ModalViewController and position it at center in iOS 7
body: <p>I am trying to show a modalView on an iPad by reducing its width and height, but the problem is that it is not center-aligned. In iOS 6 it used to work fine, but in iOS 7 it is not center aligned.</p>
  
  <p>Below is my code:</p>
  
  <pre><code> m_helpQA = [[HelpQAViewController alloc]init];
  
   m_helpQA.modalPresentationStyle = UIModalPresentationFormSheet;      
  
   [self presentViewController:m_helpQA animated:YES completion:NULL];
   m_helpQA.view.superview.bounds = CGRectMake(0, 0, 350, 250);//Dimensions of ModalView.
  </code></pre>
  
  <p>presently I am getting it this way</p>
  
  <p><img src="https://i.stack.imgur.com/YVxPp.png" alt="enter image description here"></p>