title: XCode : How to get resize view buttons in interface builder
body: <p>I opened an old project in Xcode 6 Version 6.0 (6A279r).</p>
  
  <p>For certain .xib files IB is showing resize-view buttons as follows:
  <img src="https://i.stack.imgur.com/V4Ttx.png" alt="enter image description here"></p>
  
  <p>But, for certain .xib files IB is not showing resize-view buttons:
  <img src="https://i.stack.imgur.com/nceSC.png" alt="enter image description here"></p>
  
  <p>How can I enable the missing resize view buttons?</p>