title: Set a RGBA color to a layout
body: <p>I've a Layout which has a bg color customized by user. User fills 4 values.
  R-G-B-Alpha</p>
  
  <p>But, I've seen that the method to set the color in a layout, doesnt accept 4 values.
  <code>setBackgroundColor()</code> just accepts int value.</p>
  
  <p>I've searched for a java parser, from RGBA to HEX but I couldn't find any.</p>
  
  <p>Do you know guys where could I find one?</p>
  
  <p>Thanks.</p>