title: UIScrollView + Centered View + Ambigous Scrollable Content Size + many iPhone sizes
body: <p>I have:</p>
  
  <ul>
  <li>application, that should work in landscape and portrait mode.</li>
  <li>view with full-size scroll view on top.</li>
  <li>some view inside scroll view with fixed width and height. (with added H and W constraints)</li>
  <li>set to view inside scroll view as horizontal centered in container. (added according constraint)</li>
  </ul>
  
  <p>I have warning in interface builder "Has ambiguous scrollable content width".
  <img src="https://i.stack.imgur.com/M2tde.png" alt="enter image description here"></p>
  
  <p>The only way to fix this problem, that I know - is set trailing and leading constraints.
  But for different iPhones (5.5", 4.7", 4") I need to set different trailing and leading constraints.</p>
  
  <p>How can I eliminate this warning and still have centered horizontally view with fixed W and H for all iPhone sizes?</p>
  
  <p>I create Github repo to illustrate this problem: <a href="https://github.com/skywinder/scrollViewAmbigous" rel="noreferrer">ScrollViewAmbigous</a></p>
  
  <p><em>This is not duplicate of <a href="https://stackoverflow.com/questions/19036228/uiscrollview-scrollable-content-size-ambiguity-xcode-5-ios-7-interface-builder">UIScrollView Scrollable Content Size Ambiguity</a>
  , but it similar (and not answered although), but this question especially related to different sizes of iPhones.</em></p>