بهترین مدیریت دولت برای توسعه دهندگان جدید Flutter: با یک مثال راهنمای اولیه

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: CounterScreen(),
    );
  }
}

class CounterScreen extends StatefulWidget {
  @override
  _CounterScreenState createState() => _CounterScreenState();
}

class _CounterScreenState extends State<CounterScreen> {
  int _count = 0;

  void _increment() {
    setState(() {
      _count++;
    });
  }

  void _decrement() {
    setState(() {
      _count--;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('Counter App')),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Text('Count: $_count'),
            Row(
              mainAxisAlignment: MainAxisAlignment.center,
              children: [
                IconButton(icon: Icon(Icons.remove), onPressed: _decrement),
                IconButton(icon: Icon(Icons.add), onPressed: _increment),
              ],
            ),
          ],
        ),
      ),
    );
  }
}

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

class Counter with ChangeNotifier {
  int _count = 0;

  int get count => _count;

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

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

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: CounterScreen(),
    );
  }
}

class CounterScreen extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('Provider Example: Counter')),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Text('Count:'),
            Consumer<Counter>(
              builder: (context, counter, child) {
                return Text('${counter.count}');
              },
            ),
            Row(
              mainAxisAlignment: MainAxisAlignment.center,
              children: [
                IconButton(
                  icon: Icon(Icons.remove),
                  onPressed: () => context.read<Counter>().decrement(),
                ),
                IconButton(
                  icon: Icon(Icons.add),
                  onPressed: () => context.read<Counter>().increment(),
                ),
              ],
            ),
          ],
        ),
      ),
    );
  }
}

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

final counterProvider = StateNotifierProvider<Counter, int>((ref) => Counter());

class Counter extends StateNotifier<int> {
  Counter() : super(0);

  void increment() => state++;
  void decrement() => state--;
}

void main() {
  runApp(ProviderScope(child: MyApp()));
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: CounterScreen(),
    );
  }
}

class CounterScreen extends ConsumerWidget {
  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final count = ref.watch(counterProvider);
    return Scaffold(
      appBar: AppBar(title: Text('Riverpod Example: Counter')),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Text('Count: $count'),
            Row(
              mainAxisAlignment: MainAxisAlignment.center,
              children: [
                IconButton(
                  icon: Icon(Icons.remove),
                  onPressed: () => ref.read(counterProvider.notifier).decrement(),
                ),
                IconButton(
                  icon: Icon(Icons.add),
                  onPressed: () => ref.read(counterProvider.notifier).increment(),
                ),
              ],
            ),
          ],
        ),
      ),
    );
  }
}

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

class CounterController extends GetxController {
  var count = 0.obs;

  void increment() => count++;
  void decrement() => count--;
}

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: CounterScreen(),
    );
  }
}

class CounterScreen extends StatelessWidget {
  final CounterController controller = Get.put(CounterController());

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('GetX Example: Counter')),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Text('Count:'),
            Obx(() => Text('${controller.count}')),
            Row(
              mainAxisAlignment: MainAxisAlignment.center,
              children: [
                IconButton(
                  icon: Icon(Icons.remove),
                  onPressed: controller.decrement,
                ),
                IconButton(
                  icon: Icon(Icons.add),
                  onPressed: controller.increment,
                ),
              ],
            ),
          ],
        ),
      ),
    );
  }
}