Using Provider for State Management

This example demonstrates how to use the Provider package for state management in a Flutter app.

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

void main() {
  runApp(
    ChangeNotifierProvider(
      create: (context) => Counter(),
      child: MyApp(),
    ),
  );
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Provider Example',
      theme: ThemeData(primarySwatch: Colors.blue),
      home: CounterScreen(),
    );
  }
}

class Counter with ChangeNotifier {
  int _count = 0;

  int get count => _count;

  void increment() {
    _count++;
    notifyListeners();
  }

  void decrement() {
    _count--;
    notifyListeners();
  }
}

class CounterScreen extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('Counter')),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            Text('Count: ${context.watch<Counter>().count}'),
            Row(
              mainAxisAlignment: MainAxisAlignment.center,
              children: [
                ElevatedButton(
                  onPressed: () => context.read<Counter>().decrement(),
                  child: Text('-'),
                ),
                SizedBox(width: 20),
                ElevatedButton(
                  onPressed: () => context.read<Counter>().increment(),
                  child: Text('+'),
                ),
              ],
            ),
          ],
        ),
      ),
    );
  }
}