Flutter 入门：第一个 Hello World 程序

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget { @override Widget build(BuildContext context) { return MaterialApp( title: 'Hello World', home: Scaffold( appBar: AppBar( title: Text('Hello World'), ), body: Center( child: Text('Hello, World!'), ), ), ); } }