class MyText extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Text("นี่คือ Stateless");
  }
}

class MyCounter extends StatefulWidget {
  @override
  _MyCounterState createState() => _MyCounterState();
}

class _MyCounterState extends State<MyCounter> {
  int count = 0;

  void increment() {
    setState(() {
      count++;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Column(
      mainAxisSize: MainAxisSize.min,
      children: [
        Text('จำนวน: \$count', style: TextStyle(fontSize: 24)),
        ElevatedButton(onPressed: increment, child: Text("เพิ่ม"))
      ],
    );
  }
}

import 'package:flutter/material.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(title: Text("StatefulWidget Example")),
        body: Center(child: MyCounter()),
      ),
    );
  }
}

class MyCounter extends StatefulWidget {
  @override
  _MyCounterState createState() => _MyCounterState();
}

class _MyCounterState extends State<MyCounter> {
  int count = 0;

  void increment() {
    setState(() {
      count++;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Column(
      mainAxisAlignment: MainAxisAlignment.center,
      children: [
        Text('คุณกดแล้ว: \$count ครั้ง', style: TextStyle(fontSize: 20)),
        SizedBox(height: 10),
        ElevatedButton(
          onPressed: increment,
          child: Text("กดเพิ่ม")
        )
      ],
    );
  }
}