title: Flutter: show asset gif in alert dialog
body: <p>I am trying to show this gif asset in my alert dialog, but get an error:</p>
  <pre><code>Another exception was thrown: Unable to load asset: assets/tutorial/lip.gif
  </code></pre>
  <p>But .png images work fine.</p>
  <p>Here is my code for the alert dialog:</p>
  <pre><code>...
  AlertDialog(
          title: Text('Showing Lip'),
          content: Container(
            child: Image.asset(
              'assets/tutorial/lip.gif',
              height: 125.0,
              width: 125.0,
            ),
          ),
  ...
  </code></pre>
  <p>Any help is appreciated!</p>