title: Showing preference screen first time app is run and related questions
body: <p>I have an app with 2 activities, the preference and the main activity, I need the preference screen to show first time the app is run so the user can do some configuration. I have checked through the answers on this topic and they don't seem very clear but I gather it has to do with checking that there are sharedpreference file is empty.</p>
  
  <p>Can someone please give me a code to sort this out and on which activity would I put the code?
  Also I am still in the developing stage so I already have my preferences setup how do I undo this?</p>
  
  <p>Thanks in Advance</p>