title: error: The argument type 'MaterialPageRoute' can't be assigned to the parameter type 'Route<Map>'
body: <p>I am learning flutter and this code is straight from the teacher. I know that flutter changing all the time and this may be why it is not running. anyways here it is:</p>
  
  <pre><code>class Klimatic extends StatefulWidget {
    @override
    _KlimaticState createState() =&gt; new _KlimaticState();
  }
  
  class _KlimaticState extends State&lt;Klimatic&gt; {
  
    String _cityEntered;
  
    Future _goToNextScreen(BuildContext context) async {
      Map results = await Navigator
          .of(context)
          .push(new MaterialPageRoute&lt;dynamic&gt;(builder: (BuildContext context) {
        return new ChangeCity();
      }));
  
      if ( results != null &amp;&amp; results.containsKey('enter')) {
         _cityEntered = results['enter'];
  
  //      debugPrint("From First screen" + results['enter'].toString());
  
  
      }
    }
  </code></pre>