title: React native camera going blank on navigation
body: <p>I'm using expo's Camera module and react native navigation to go from a simple Stack navigator where I have:</p>
  
  <pre><code>--Add
  --Home
  --Profile
  </code></pre>
  
  <p>On using the Camera module in the Add tab, i'm able to view the camera perfectly one time, however switching tabs and coming back gives me a blank view till I refresh the app again.. I understand that expo only supports one camera, and I do have only one instance running in the app.. I can also see that my components are not unmounted on tab switch, which is something needed inorder to maintain the state. I looked at react navigation's <code>reset()</code> but their official docs are down and none of the comments are useful enough.. Can someone explain how to kill that component on switch or just to make the camera work after switching? </p>