title: Remove background colour from FloatingActionButton
body: <p>I am using several FloatingActionButton in my application as :</p>
  
  <pre><code>    &lt;android.support.design.widget.FloatingActionButton
          android:id="@+id/loc_button"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:layout_gravity="bottom|end"
          android:layout_marginBottom="123dp"
          android:layout_marginEnd="@dimen/mini_fab_margin"
          android:src="@drawable/plus"
          app:backgroundTint="@android:color/black"
          app:elevation="2dp"
          app:fabSize="mini"/&gt;
  </code></pre>
  
  <p>Where plus.png is a small plus image with transparent background.</p>
  
  <p>I know FloatingActionButton by default picks up colorPrimary of your applicaytion set in colors.xml</p>
  
  <p>I know we can change the colour via tag :</p>
  
  <pre><code>    app:backgroundTint="@android:color/black"
  </code></pre>
  
  <p>But can we remove colour? I mean can we have an Image with background colour in FloatingActionButton,</p>
  
  <p>I tried using </p>
  
  <pre><code>    app:backgroundTint="@android:color/transparent"
  </code></pre>
  
  <p>But it still displays black shadow around image. How can we remove this and display just the image without any background.
  ?</p>
  
  <p>This is what  app:backgroundTint="@android:color/transparent" and style : style="?android:attr/borderlessButtonStyle" makes it look like : </p>
  
  <p><a href="https://i.stack.imgur.com/AA8h7.png" rel="noreferrer"><img src="https://i.stack.imgur.com/AA8h7.png" alt="look for transparent circle because of shadow"></a></p>
  
  <p>Look for transparent circle around because of shadow. It is here that I can not get rid of shadow but I want shadow to be around image.</p>