title: The member 'notifyListeners' can only be used within 'package:flutter/src/foundation/change_notifier.dart' or a test
body: <p>I am using ChangeNotifier and i change their value and notify like below,</p>
  <pre><code>// Declare
  ValueNotifier&lt;bool&gt; isDisplay = new ValueNotifier(false);
  
  // Change value
  isDisplay.value = false;
  isDisplay.notifyListeners();
  
  </code></pre>
  <p>It's working fine. but it's raise warning like below,
  <a href="https://i.stack.imgur.com/bOfah.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/bOfah.png" alt="enter image description here" /></a></p>
  <p>Can we resolve this using proper implementation or other things ?</p>