title: save/restore fragment stack on Activity destroyed
body: <p>In my project, there are Activities and Fragments. And there's an Fragment backstack. </p>
  
  <p>My question is how to save/restore the fragment stack in case of Activity is destroyed by the OS.</p>
  
  <hr>
  
  <p>@forcewill are you taling about addToBackStack? Yes I did. I'm not talking about popup topmost fragment in case of back pressed. I'm talking about to restore the fragment stack in case of Activity destroyed.</p>
  
  <hr>
  
  <p>@Derek, I did follow your way to write the following to every fragment and activity to override onStaveInstanceState(...)</p>
  
  <pre><code>@Override
  protected void onSaveInstanceState(Bundle outState) {
      super.onSaveInstanceState(outState);
  }
  </code></pre>
  
  <p>But it seems like it's still not working.</p>
  
  <p>I have tested on 
   - Galaxy S3 with Android 4.1
   - Emulator with Android 5.1 (to turn a debugging option named "Don't keep activity"</p>
  
  <hr>
  
  <p>@josedlujan, it's not about save single Fragment instance, it's about save the fragments in stack.</p>