title: implement the iOS round button in Android
body: <p>I am trying to create the iOS round button in Android. As you may know, Android buttons have grey background while the iOS round button has a clear background. I should use styles and themes to achieve this. </p>
  
  <p>However, I do not know how to piece things together. Could anyone please give some advice?</p>
  
  <p>Thanks</p>