Could not find a generator for route : <p>I´m newbie to flutter and reveice one exception about route and paginator in Flutter.</p>

<pre><code>EXCEPTION CAUGHT BY GESTURE
The following assertion was thrown while handling a gesture:
Could not find a generator for route "/listadecompras" in the _MaterialAppState.
</code></pre>

<p>Follow a excerpt from code:</p>

<pre><code>import 'package:flutter/material.dart';

class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return new MaterialApp(
// ...                    
                return new ListTile(
                  onTap: () {                                         
                    Navigator.pushNamed(context, "/listadecompras");
                  },
// ...
}


class ListaDeCompras extends StatelessWidget {
@override
Widget build(BuildContext context) {
return new Scaffold(
// ...
}
}


void main() {
runApp(new MaterialApp(
    home: new MyApp(), 
    routes: &lt;String, WidgetBuilder&gt;{
        "/listadecompras": (BuildContext context) =&gt; new ListaDeCompras()
    }
));
}
</code></pre>

<p>Please, someone could send some advice?
thanks in advance for your attention</p>
