title: Floating action button and white background
body: <p>In fact, I search a way to mimic the FAB's inbox. When user press the red button, an opac view and a menu should appear. Because images are more more meaningful, see the following picture</p>
  
  <p><img src="https://i.stack.imgur.com/BHzxI.png" alt="enter image description here"></p>
  
  <p>I know it exists this wonderful library (<a href="https://github.com/futuresimple/android-floating-action-button" rel="noreferrer">https://github.com/futuresimple/android-floating-action-button</a>) and with this library, i can display floating action menu. But my problem is displaying the white background (with opacity). I didn't find a solution to solve my problem ...</p>
  
  <p>Thx in advance</p>