title: Android animation for corner radius
body: <p><strong>What I want to achieve</strong></p>
  
  <p>I have an application, where in the bottom left corner, I have a button. This button is a circular ImageButton. When I press the button (with the magnifying glass icon, the following transition should happen: </p>
  
  <p><a href="https://i.stack.imgur.com/mBkYV.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/mBkYV.jpg" alt="Left shows start, right show finish"></a></p>
  
  <p>Also, if it is not clear in the image, the button is a ImageButton, while the "end result" is a SearchView. This doesn't necessarily have to be like this, but it seems to be the best way to go.</p>
  
  <p><strong>What I have now</strong></p>
  
  <p>I have an XML-file for the style of the circular button, called <em>search_button_layout.xml</em> that looks like this:</p>
  
  <pre><code>    &lt;?xml version="1.0" encoding="utf-8"?&gt; shapexmlns:android="http://schemas.android.com                        /apk/res               /android"     android:shape="rectangle"
  android:layout_height="wrap_content"
  android:layout_width="wrap_content"&gt;
  &lt;corners
      android:topLeftRadius="100dp"
      android:topRightRadius="100dp"
      android:bottomLeftRadius="100dp"
      android:bottomRightRadius="100dp"
      /&gt;
  &lt;solid
      android:color="#31DE65"
      /&gt;
  &lt;padding
      android:left="0dp"
      android:top="0dp"
      android:right="0dp"
      android:bottom="0dp"
      /&gt;
  &lt;size
      android:width="45dp"
      android:height="46dp"
      /&gt;
  &lt;/shape&gt; 
  </code></pre>
  
  <p>The button itself is created in the <em>activity_main.xml</em> file, and looks like this.</p>
  
  <pre><code>    &lt;ImageButton
  
      android:id="@+id/search_btn"
      android:layout_width="65dp"
      android:layout_height="66dp"
      android:background="@layout/search_button_layout"
      android:layout_alignParentBottom="true"
      android:layout_alignParentLeft="true"
      android:onClick="goToSearch"
      android:src="@drawable/ic_action_name"
      android:scaleType="fitCenter" /&gt;
  </code></pre>
  
  <p>I have been trying to search, but I only end up with unanswered questions that are outdated.</p>
  
  <p>Please respond if informations is lacking, or if you have a source to a solution that I haven't been able to find.</p>
  
  <p><strong>Short version</strong></p>
  
  <p>When I click the circular imagebutton (left in the image) I want an animation that looks like a searchview (right in the image).</p>