Could not find a generator for route - flutter

Question

I´m newbie to flutter and reveice one exception about route and paginator in Flutter.
EXCEPTION CAUGHT BY GESTURE
The following assertion was thrown while handling a gesture:
Could not find a generator for route "/listadecompras" in the _MaterialAppState.
Follow a excerpt from 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: <String, WidgetBuilder>{
"/listadecompras": (BuildContext context) => new ListaDeCompras()
}
));
}
Please, someone could send some advice?
thanks in advance for your attention

Answer 1

Because Of instantiated two MaterialApp widgets. You need to remove the one in MyApp class and may change it to Scaffold
Example:
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return new Scaffold(
// ...
return new ListTile(
onTap: () {
Navigator.pushNamed(context, "/listadecompras");
},
// ...
}
THE PROBLEM IS YOUR CODE IS - the route is trying to resolve for the nearest MaterialApp which has no route definition. That said you should use only one MaterialApp as the root of your widget tree.

Answer 2

try this :
onPressed: () {
Navigator.push(
context,
new MaterialPageRoute(
builder: (context) => new ListaDeCompras(),
),
);
},

Answer 3

If a new file is created and you are defining a route for that new file, its better to re-run the app rather than hot reloading.It worked for me!

Answer 4

flutter clean and run again, is working for me.

Answer 5

I had a similar issue because I defined the route as '/listadecompras' and then called Navigator.pushNamed(context, "listadecompras"); without the forward slash.
It isn't probably the same scenario than this question but it shows the same error.

Answer 6

It happened to me, but in my case there was a single MaterialApp widget instantiated, so I wasn't able to find the cause.
I noticed that in my App, all calls to Navigator where done the same, with:
Navigator.of(context).pushNamed('/route-name');
All, except the first one, which was like this:
Navigator.pushNamed(context, '/route-name');
After changing the above line to be equal to the others (using .of(context)), the problem got solved!
Note
Until now I had no problems with navigation, it happened once tried to navigate to a new view from a dialog.
If you have only one MaterialApp, and you cannot fix this issue, try to check your navigation chain, and use the same way of calling Navigator in every place.
Bye

Answer 7

#aziza is the right answer
but in some miscellaneous situation
in my case
class RouteGenerator {
static Route<dynamic> generateRoute(RouteSettings settings) {
switch (settings.name) {
case '/':
MaterialPageRoute(builder: (_) => MyScaffold());
break;
case '/homechart':
MaterialPageRoute(builder: (_) => analytics());
break;
}
}
}
I forget to return keyword and IDE not showing any error. showing this kind of error.
Solution is like this :
class RouteGenerator {
static Route<dynamic> generateRoute(RouteSettings settings) {
switch (settings.name) {
case '/':
return MaterialPageRoute(builder: (_) => MyScaffold());
break;
case '/homechart':
return MaterialPageRoute(builder: (_) => analytics());
break;
}
}
}

Answer 8

You have instantiated two MaterialApp widget. You need to remove the one in MyApp class.
For push
Navigator.of(context).pushNamed('/screen1')
For Pop: "popAndPushNamed"
Navigator.of(context).popAndPushNamed('/screen4');

Answer 9

I have encountered the same error and solved by just restarting the app

Answer 10

In my case the error was because i deleted the route from main.dart and forgot the update the change in other files

Answer 11

I had the same error i don't know why flutter does that after creating a new screen but all you need is rebuild zor re-run the app again

Answer 12

There need to be only one MaterialApp if you have multiple MaterialApps then I would recommend to keep only one MaterialApp for your project.

Answer 13

I had the same problem. the problem was that I had a template and had duplicated the screens and didn't delete my materialapps after everything worked tanks a lot

Answer 14

I recently had the same problem any way I managed to resolve it by using Global Key
the context which I need to navigate from was the problem because it refers to a widget not a page that holds this widget so I made static GlobalKey appKey = GlobalKey();
then use it in the scaffold of the page then i can use its context from any place in the app MainPage.appKey.currentContext;

Answer 15

One of the solutions would be hot restarting your code.
That is because we declare the route name outside the Widget Build.

Answer 16

If you don't have a home property defined for your MaterialApp, you probably should have this kind of error. Please try to fill it with a Scaffold widget.