import 'package:flutter/material.dart';

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

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

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: const CounterScreen
    );
  }
}

class CounterScreen extends StatefulWidget {
  const CounterScreen({super.key});

  @override
  State<CounterScreen> createState() => _CounterScreenState();
}

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

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

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('Счётчик')),
      body: Center(
        child: Text(
          'Значение: $_count',
          style: Theme.of(context).textTheme.headlineMedium,
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _increment,
        tooltip: 'Добавить',
        child: const Icon(Icons.add),
      ),
    );
  }
}