title: Make an android activity full screen over a button
body: <p>Im new on android development and I want to know how can I make an android activity fullscreen via a Icon placed on toolbar.</p>
  
  <p>Thank You.</p>
  
  <p>Please click on link for example image:
  <a href="http://i.stack.imgur.com/udJRl.jpg" rel="nofollow">Click to preview example</a></p>