title: Flutter Custom Animated Icon
body: <p>I am looking to make a item that gets added and removed from list.</p>
  <p>what I am looking for is to have the + icon and the - icon and animate between the 2 for a clean and smooth look.</p>
  <p>I have the following code</p>
  <pre><code>Container(
              padding: EdgeInsets.fromLTRB(0, 0, 20, 0),
              child: AnimatedIcon(
                icon: AnimatedIcons.home_menu,
                progress: _animationController,
                color: Colors.white,
              ))
  </code></pre>
  <p>with</p>
  <pre><code>void _handleOnPressed() {
  setState(() {
    isPlaying = !isPlaying;
    isPlaying
        ? _animationController.forward()
        : _animationController.reverse();
    });
  }
  </code></pre>
  <p>This for fine for the built in animated icons in flutter.</p>
  <p>I am looking to use the + and the - icon, but with the same look.</p>
  <p>Is there a way to do this?</p>