nested_provider_scope.dart

import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';

final provider = StateNotifierProvider<SomeProvider, String>(
    (_) => throw UnimplementedError());
void main() => runApp(const MyApp());

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return const MaterialApp(title: 'Material App', home: Home());
  }
}

class Home extends StatefulWidget {
  const Home({
    Key? key,
  }) : super(key: key);

  @override
  State<Home> createState() => _HomeState();
}

class _HomeState extends State<Home> {
  /// Your api call
  final _future =
      Future<String>.delayed(const Duration(seconds: 3), () => 'Data arrived');
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('Material App Bar')),
      body: Center(
        child: FutureBuilder<String>(
          future: _future,
          builder: (context, snapshot) {
            if (snapshot.connectionState == ConnectionState.done) {
              return ProviderScope(
                overrides: [
                  provider.overrideWithValue(SomeProvider(snapshot.data!))
                ],
                child: const SomeWidget(),
              );
            } else {
              return const CircularProgressIndicator();
            }
          },
        ),
      ),
    );
  }
}

class SomeWidget extends ConsumerWidget {
  const SomeWidget({
    Key? key,
  }) : super(key: key);
  @override
  Widget build(BuildContext context, ScopedReader watch) {
    return Column(
      mainAxisAlignment: MainAxisAlignment.center,
      children: [
        Text(watch(provider)),
        const SizedBox(height: 10),
        ElevatedButton(
          child: const Text('Change'),
          onPressed: context.read(provider.notifier).changeDataToSomething,
        ),
      ],
    );
  }
}

class SomeProvider extends StateNotifier<String> {
  final String somedataFromApi;

  SomeProvider(this.somedataFromApi) : super(somedataFromApi);

  void changeDataToSomething() {
    state = 'Data changed';
  }
}