Provider: Could not find the correct Provider<Bloc> above this ChangeStringWithButton Widget

[kushtra24]

Hi, this probably isn't a bug, but I don't understand what is going on here.

I get thouse 2 errors:

- Could not find the correct Provider<SecondPageBloc> above this ChangeStringWithButton Widget
- There are multiple heroes that share the same tag within a subtree.

This is my MultiProvider at the Myapp() main page:

home: MultiProvider(
        providers: [
          Provider<CounterBloc>(
            value: CounterBloc(),
          ),
          Provider<UserBloc>(
            value: UserBloc(),
          ),
          Provider<SecondPageBloc>(
            value: SecondPageBloc(),
          ),
        ],
        child: BlocCounterPage(), // the main page
      ),

depending on the child ^ which i am using in the MultiProvider that widget is working but if I navigate to another page with the drawer I get the error mentioned above

The Navigation from the Drawer:

Divider(height: 2.0, color: Colors.blue,),
          ListTile(
              leading: Icon(Icons.text_fields),
              title: Text('Change Text with button'),
              onTap: () {
                Navigator.of(context).pushReplacement(
                    MaterialPageRoute(builder: (BuildContext context) {
                      return ChangeStringWithButton();
                    }));
              }
          ),

This is a simple counter bloc

import 'dart:async';
import 'package:rxdart/rxdart.dart';
import 'package:simple_bloc/api/db_api.dart';
import 'package:simple_bloc/models/user.dart';

class UserBloc {
  User _user;
  final _userController  = BehaviorSubject<User>();
  Stream<User> get outUser => _userController.stream;
  UserBloc(){
    init();
  }
  void init() async {
    _user = await api.getUser();
    _userController.add(_user);
  }
  void updateUser(User user){
    _user = user;
    _userController.add(_user);
  }
}

Another thing If I use pushReplacment to navigate I get a big error:
Could not find the correct Provider<SecondPageBloc> above this ChangeStringWithButton Widget

[rrousselGit]

This happens because you added your providers on home field instead of wrapping the entire MaterialApp

As such, other routes cannot access providers.

In your case,
DO:

Provider<int>(
  value: 42,
  child: MaterialApp(home: Home()),
)

DON'T:

MaterialApp(
  home: Provider<int>(
    value: 42,
    child: Home(),
  ),
)

[kushtra24]

Thanks, that is correct, one more question:
I am still getting an issue (a blank black page) when I use "push" on the navigator instead of "pushReplacement"

ListTile(
            leading: Icon(Icons.settings),
            title: Text('Settings'),
            onTap: () => Navigator.of(context).push(
                MaterialPageRoute(builder: (BuildContext context) {
                  return ThemeSwitcher();
                })),
          ),

Error:
There are multiple heroes that share the same tag within a subtree.

[rrousselGit]

That's unrelated to provider package. You may want to ask that on StackOverflow instead

[livingstonex]

keeps giving me this error: Error: Could not find the correct Provider above this MyApp Widget

`import 'package:api_work/authentication_service.dart';
import 'package:provider/provider.dart';

void main() => runApp(
ChangeNotifierProvider(
child: MyApp(),
builder: (BuildContext context){
return AuthService();
},

),
);

class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return new MaterialApp(
debugShowCheckedModeBanner: false,
home: FutureBuilder(
// get the Provider, and call the getUser method
future: Provider.of(context).getUser(),
// wait for the future to resolve and render the appropriate
// widget for HomePage or LoginPage
builder: (context, AsyncSnapshot snapshot) {
if (snapshot.connectionState == ConnectionState.done) {
return snapshot.hasData ? HomePage() : LoginPage();
} else {
return Container(color: Colors.white);
}
},
),
);
}
}

`

[livingstonex]

Error: Could not find the correct Provider above this MyApp Widget``

[rrousselGit]

You must specify the type of the object you want to obtain when calling Provider.of.

[janosdupai]

I also have an issue....

I try to trigger a simple action from a different class, using provider package. What I did:

1) I created a ChangeNotifier class named MySchedule which has a getter and a setter:

class MySchedule extends ChangeNotifier {
   bool _foodSet = false;
   bool get foodSet => _foodSet;
   set foodSet(bool newBool) {
    _foodSet = newBool;
    notifyListeners();
   }
}

The widget tree of this widget is the following (I made it shorter, than the original) - this is inside a stateful widget class

  @override
  Widget build(BuildContext context) {

    return  ChangeNotifierProvider(
        builder: (context) => MySchedule(),
    child: Scaffold(
        body: Stack(
      children: <Widget>[
        Container(
          child: AnotherWidgetWhichHasLotOfChild()
          ),
        ),
        AnimatedContainer(
          curve: Curves.fastOutSlowIn,
          duration: Duration(milliseconds: 500),
          alignment: Alignment(left, -1),
          child: MenuSheet(close: toggleMainMenu, change: changeToTab),
        ),
        FoodDetailsClass()
      ],
        ),
      ));
  }

The FoodDetailsClass has a container in a visibility, which 'visible' boolean I want to change with the provider:

class FoodDetailsClass extends StatelessWidget {

  @override
  Widget build(BuildContext context) {


    return Consumer<MySchedule>(
        builder: (context, provider, child) => Visibility(
      visible: provider.foodSet,
      child: Center(
        child: Container(
          height: 600,
          width: 400,
          color: Colors.red,
        ),
      ),
    ));
  }
}

I want to change it from inside the "AnotherWidgetWhichHasLotOfChild()" class in this way: Inside the above mentioned class there is a following call (but it throws an error):

GestureDetector(
      onTap: (){
        final schedule2 =
        Provider.of<MySchedule>(context);
        schedule2.foodSet = true;
      }

The error is: Error: Could not find the correct Provider above this FoodList Widget

To fix, please:

Ensure the Provider is an ancestor to this FoodList Widget

[beiger]

@janosdupai
I have the same problem, have you fix it?

[amolshinde07]

I have an issue.

When i open up the drawer from the below code it says that " Could not find the correct Provider above this SettingsForm Widget"

class _SettingsFormState extends State {
final _formkey = GlobalKey();
final List sugars=['0''1','2','3','4'];

//form value
String _currentName='';
String _currentSugars=null;
int _currentStrength;
@override
Widget build(BuildContext context){

final user=Provider.of(context);

return StreamBuilder<UserData>(
  stream: DatabaseService(uid: user.uid).userData,
  builder: (context, snapshot) {

    if(snapshot.hasData){

      UserData userData=snapshot.data;

      return Form(
          key: _formkey,
          child: Column(
            children: <Widget>[
              Text(
                'Update your Brew Settings',
                style: TextStyle(
                    fontSize: 18.0
                ),
              ),
              SizedBox(
                height: 20,
              ),
              TextFormField(
                initialValue: userData.name,
                decoration: textInputDecoration,
                validator: (val)=>val.isEmpty?'Please enter a name':null,
                onChanged: (val)=>setState(()=>_currentName=val),
              ),
              SizedBox(
                height: 20,
              ),
              DropdownButtonFormField(
                decoration: textInputDecoration,
                value: _currentSugars ?? userData.sugars,
                items: sugars.map((sugar){
                  return DropdownMenuItem(
                    value: sugar,
                    child: Text(
                        '$sugar sugar'
                    ),

                  );
                }).toList(),
                onChanged: (value) => setState(() => _currentSugars = value ),
              ),
              Slider(
                value: (_currentStrength??100).toDouble(),
                min: 100,
                max: 900,
                divisions: 8,
                activeColor: Colors.brown[_currentStrength??100],
                inactiveColor: Colors.brown[_currentStrength??100],
                onChanged: (value) => setState(() => _currentStrength = value.round() ),
              ),

              RaisedButton(
                color: Colors.pink[400],
                child: Text(
                  'Update',
                  style: TextStyle(
                      color: Colors.white
                  ),
                ),
                onPressed:()async{
                  print(_currentName);
                  print(_currentSugars);
                  print(_currentStrength);
                },
              )
            ],
          ),
        );
    }
    else{
      return null;

    }

  }
);

}
}

[jhbiggs]

I had the same problem with a Medium tutorial. You might try adding your type after "Provider.of", i.e.: Provider.of<AuthService>(context).

[jhasan94]

I'm facing a similar problem. My code is given below

class MyApp extends StatelessWidget {
  final geoService = GeolocatorService();
  @override
  Widget build(BuildContext context) {
    return FutureProvider<dynamic>(
      create: (context) async => geoService.getInitialLocation(),
      child: MaterialApp(
        home: Consumer<Position>(
          builder: (context, position, widget) {
            return Maps(position);
          },
        ),
      ),
    );
  }
}

Error: Could not find the correct Provider<Position> above this Consumer<Position> Widget

[rrousselGit]

Change your code to FutureProvider<Position>