I am trying to run sample Riverpod program from Getting started Riverpod page
Pubspec is specified as given on the page.
Debug Console dumps the following message:
Launching lib/main.dart on Chrome in debug mode...
lib/main.dart:1
: Error: Method not found: 'Error.throwWithStackTrace'.
../…/framework/provider_base.dart:985
Error.throwWithStackTrace(error, chain);
^^^^^^^^^^^^^^^^^^^
: Error: A non-null value must be returned since the return type 'Never' doesn't
allow null.
../…/framework/provider_base.dart:979
Never _rethrowProviderError(Object error, StackTrace stackTrace) {
^
Failed to compile application.
Exited (sigterm)
Just to be sure, following is main.dart:
import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
// We create a "provider", which will store a value (here "Hello world").
// By using a provider, this allows us to mock/override the value exposed.
final helloWorldProvider = Provider((_) => 'Hello world');
void main() {
runApp(
// For widgets to be able to read providers, we need to wrap the entire
// application in a "ProviderScope" widget.
// This is where the state of our providers will be stored.
const ProviderScope(
child: MyApp(),
),
);
}
// Extend ConsumerWidget instead of StatelessWidget, which is exposed by Riverpod
class MyApp extends ConsumerWidget {
const MyApp({Key? key}) : super(key: key);
@override
Widget build(BuildContext context, WidgetRef ref) {
final String value = ref.watch(helloWorldProvider);
return MaterialApp(
home: Scaffold(
appBar: AppBar(title: const Text('Example')),
body: Center(
child: Text(value),
),
),
);
}
}
And pubspec is as follows:
name: simple_app
description: A new Flutter project.
publish_to: 'none' # Remove this line if you wish to publish to pub.dev
version: 1.0.0+1
environment:
sdk: ">=2.12.0 <3.0.0"
flutter: ">=2.0.0"
dependencies:
flutter:
sdk: flutter
flutter_riverpod: ^2.0.0-dev.4
cupertino_icons: ^1.0.2
dev_dependencies:
flutter_test:
sdk: flutter
flutter_lints: ^1.0.0
flutter:
uses-material-design: true
Environment: Flutter (Channel stable, 2.5.3, on macOS 12.2.1 21D62 darwin-x64, locale en-US)