Learn Flutter

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(
      title: 'Hello Flutter',
      home: Scaffold(
        appBar: AppBar(title: const Text('My App')),
        body: const Center(
          child: Text(
            'Hello, World!',
            style: TextStyle(fontSize: 24),
          ),
        ),
      ),
    );
  }
}

App runs on device/emulator:
─ AppBar: "My App"
─ Body:   "Hello, World!" — centred

class CounterApp extends StatefulWidget {
  const CounterApp({super.key});
  @override
  State<CounterApp> createState() => _CounterState();
}

class _CounterState extends State<CounterApp> {
  int _count = 0;

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

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            Text('Count: $_count',
                style: const TextStyle(fontSize: 32)),
            ElevatedButton(
              onPressed: _increment,
              child: const Text('Tap me!'),
            ),
          ],
        ),
      ),
    );
  }
}

Initial screen: Count: 0
After 3 taps:  Count: 3
Button label:  "Tap me!"

Column(
  crossAxisAlignment: CrossAxisAlignment.start,
  children: [
    const Text('Profile',
      style: TextStyle(
        fontSize: 22,
        fontWeight: FontWeight.bold,
      ),
    ),
    const SizedBox(height: 16),
    Row(
      children: [
        const CircleAvatar(radius: 30),
        const SizedBox(width: 16),
        Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: const [
            Text('Alice Smith',
              style: TextStyle(fontWeight: FontWeight.bold)),
            Text('Flutter Developer',
              style: TextStyle(color: Colors.grey)),
          ],
        ),
      ],
    ),
  ],
)

Profile
──────────────────────
[Avatar]  Alice Smith
          Flutter Developer