This screen is a Login screen which makes the user enter into the application. I got this error although I am using the correct provider
{Error: Could not find the correct Provider above this Z Widget
To fix, please:
- Ensure the Provider is an ancestor to this Z Widget
- Provide types to Provider
- Provide types to Consumer
- Provide types to Provider.of()
- Always use package imports. Ex:
import 'package:my_app/my_code.dart';
- Ensure the correct
context
is being used.
I want to know the problem why using Provider.of(context)
does not work
import 'package:provider/provider.dart';
import 'package:voyager/api/userProvider.dart';
class LoginScreen extends StatefulWidget {
@override
_LoginScreenState createState() => _LoginScreenState();
}
class _LoginScreenState extends State<LoginScreen> {
UserProvider user_Provider;
@override
Widget build(BuildContext context) {
userProvider = Provider.of<UserProvider>(context,listen: false);
return MultiProvider(
providers: [
ChangeNotifierProvider(create: (_) => UserProvider()),
],
child: Consumer<UserProvider>(
builder: (context, userProvider, child) => Container(
child: Scaffold(
body: InkWell(
splashColor: Colors.transparent,
highlightColor: Colors.transparent,
focusColor: Colors.transparent,
onTap: () {
splash screen code
Widget build(BuildContext context) {
return Container(
child: Scaffold(
backgroundColor: AppTheme.getTheme().backgroundColor,
body:Column(
children: <Widget>[
SizedBox(
height: MediaQuery.of(context).padding.top,
),
Expanded(
child: PageView(
controller: pageController,
pageSnapping: true,
onPageChanged: (index) {
currentShowIndex = index;
},
scrollDirection: Axis.horizontal,
children: <Widget>[
PagePopup(imageData: pageViewModelData[0]),
PagePopup(imageData: pageViewModelData[1]),
PagePopup(imageData: pageViewModelData[2]),
],
),
),
PageIndicator(
layout: PageIndicatorLayout.WARM,
size: 10.0,
controller: pageController,
space: 5.0,
count: 3,
color: AppTheme.getTheme().dividerColor,
activeColor: AppTheme.getTheme().primaryColor,
),
Padding(
padding: const EdgeInsets.only(left: 48, right: 48, bottom: 8, top: 32),
child: Container(
height: 48,
decoration: BoxDecoration(
color: AppTheme.getTheme().primaryColor,
borderRadius: BorderRadius.all(Radius.circular(24.0)),
boxShadow: <BoxShadow>[
BoxShadow(
color: AppTheme.getTheme().dividerColor,
blurRadius: 8,
offset: Offset(4, 4),
),
],
),
child: Material(
color: Colors.transparent,
child: InkWell(
borderRadius: BorderRadius.all(Radius.circular(24.0)),
highlightColor: Colors.transparent,
onTap: () {
Navigator.push(
context,
MaterialPageRoute(builder: (context) => LoginScreen()),
);
},
You can register provider in ancestor widget like MyApp
and let your provider wrap MaterialApp(home: LoginScreen())
code snippet
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MultiProvider(
providers: [
ChangeNotifierProvider(create: (_) => X()),
],
child: Consumer<X>(
builder: (context, counter, _) {
return MaterialApp(
home: LoginScreen(),
);
},
),
);
}
}
full test code
import 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';
import 'package:provider/provider.dart';
void main() => runApp(MyApp());
class X with ChangeNotifier {
int _count = 0;
int get count => _count;
void increment() {
_count++;
notifyListeners();
}
}
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MultiProvider(
providers: [
ChangeNotifierProvider(create: (_) => X()),
],
child: Consumer<X>(
builder: (context, counter, _) {
return MaterialApp(
home: LoginScreen(),
);
},
),
);
}
}
class LoginScreen extends StatelessWidget {
const LoginScreen({Key key}) : super(key: key);
@override
Widget build(BuildContext context) {
final user_Provider = Provider.of<X>(context);
return Scaffold(
body: Center(
child: Column(
mainAxisSize: MainAxisSize.min,
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
const Text(
'You have pushed the button this many times:',
),
Text(
'${user_Provider.count}',
style: Theme.of(context).textTheme.display1,
),
],
),
),
floatingActionButton: IncrementCounterButton(),
);
}
}
class IncrementCounterButton extends StatelessWidget {
const IncrementCounterButton({Key key}) : super(key: key);
@override
Widget build(BuildContext context) {
return FloatingActionButton(
onPressed: () {
Provider.of<X>(context, listen: false).increment();
},
tooltip: 'Increment',
child: const Icon(Icons.add),
);
}
}
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