Provider.shared

dart

import 'package:flutter/material.dart';
import 'package:go_router/go_router.dart';
import 'package:provider/provider.dart';

void main() {
  runApp(const MyApp());
}

final _router = GoRouter(
  routes: [
    GoRoute(
      path: '/',
      builder: (context, state) => MyHomePage(title: 'Home'),
    ),
    GoRoute(
      path: '/a',
      builder: (context, state) => ScreenA(),
    ),
    GoRoute(
      path: '/b',
      builder: (context, state) => ScreenB(),
    ),
  ],
);

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return MaterialApp.router(
      routerConfig: _router,
      title: 'Home',
      theme: ThemeData(
        colorScheme: ColorScheme.fromSeed(seedColor: Colors.deepPurple),
        useMaterial3: true,
      ),
    );
  }
}

class MyHomePage extends StatelessWidget {
  const MyHomePage({super.key, required this.title});

  final String title;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(
          backgroundColor: Theme.of(context).colorScheme.inversePrimary,
          title: Text(title),
        ),
        body: Placeholder(),
        floatingActionButton: FloatingActionButton(
          onPressed: () {
            context.push('/a');
          },
          tooltip: 'to Screeb A',
          child: Text('to A'),
        ) // This trailing comma makes auto-formatting nicer for build methods.
        );
  }
}

class ScreenA extends StatelessWidget {
  const ScreenA({super.key});

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(
          title: Text('ScreenA'),
        ),
        body: Center(
          child: Provider.shared(
            create: (_) => 'This text was created on screen [A]',
            dispose: (context, value) {
              print('dispose on screen A:\nshared value => ${value}');
            },
            child: Consumer<String>(builder: (context, value, child) {
              return Text(value);
            }),
          ),
        ),
        floatingActionButton: FloatingActionButton(
          onPressed: () {
            context.push('/b');
          },
          tooltip: 'to Screen B',
          child: Text('to B'),

          // child: const Icon(Icons.add),
        ));
  }
}

class ScreenB extends StatelessWidget {
  const ScreenB({super.key});

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(
          title: Text('ScreenB'),
        ),
        body: Center(
          child: Provider.shared(
            create: (_) => 'This text was created on screen [B]',
            dispose: (context, value) {
              print('dispose on screen B:\nshared value => ${value}');
            },
            child: Consumer<String>(builder: (context, value, child) {
              return Text(value);
            }),
          ),
        ),
        floatingActionButton: FloatingActionButton(
          onPressed: () {
            context.go('/');
          },
          tooltip: 'to Screen A',
          child: Text('to Home'),

          // child: const Icon(Icons.add),
        ));
  }
}