title: .xcdatamodeld file not showing data model structure in Xcode
body: <p>I have .xcdatamodeld file in my project but it not opening up into the data model. </p>
  
  <p>When I click on the file in the left sidebar in Xcode, it continues to display the contents of the previously selected file instead of displaying the data model. Likewise, when I right click on the file and choose "Open As >", I cannot select to display it as a Data Model—nothing comes up. I checked out the code from the SVN repo and even the filer owner is not able to see it in his workspace.</p>