title: Background image for button getting stretched
body: <p>In my layout I have a button with  a background image. When  I set the width and height both to <code>wrap_content</code>, the background gets stretched. But when I use the same value for <code>dp</code> to set to width and height I get the expected result. Why is it happening?</p>
  
  <p>The image is originally circle.</p>
  
  <pre><code>           &lt;Button
              android:id="@+id/captureButton"
              android:layout_width="wrap_content"
              android:layout_height="wrap_content"
              android:layout_centerHorizontal="true"
              android:layout_centerVertical="true"
              android:background="@drawable/custom_capture" /&gt;
  </code></pre>
  
  <p>When set to wrap content for height and width</p>
  
  <p><a href="https://i.stack.imgur.com/g6QtT.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/g6QtT.png" alt="enter image description here"></a></p>
  
  <p>When set to 80dp for height and width</p>
  
  <p><a href="https://i.stack.imgur.com/cRJac.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/cRJac.png" alt="enter image description here"></a></p>