title: reset frame of relative uiimageview on hiding of another uiview ios 7
body: <p><img src="https://i.stack.imgur.com/fVU4n.png" alt="enter image description here"></p>
  
  <p>Here, in above image, <code>UIImageView</code> is inside ContainerView and ScrollView.
  There is another <code>UIView</code> at bottom of <code>UIImageView</code>, which will display Barcode.</p>
  
  <p>What I want is, 
  If Barcode will be there, <code>UIImageView</code> should be as per the ScreenShot (which is working)
  but 
  If no Barcode, <code>UIImageView</code> must be in Center of ContainerView and <code>ScrollView</code>.</p>
  
  <p>How could I implement the same, from User Interface using <code>Autolayout</code>? </p>