`import 'package:flutter/material.dart';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
        title: 'Flutter',
        theme: ThemeData(
          primarySwatch: Colors.blue,
        ),
        home: Scaffold(
          appBar: AppBar(
            title: Text("Hell Word"),
          ),
          body: Center(
            child: Text(
              //设置内容
              "Hello Word2Hello Word2Hello Word2Hello Word2Hello Word2Hello Word2Hello Word2Hello Word2Hello Word2",
              //对齐方式
              textAlign: TextAlign.left,
              // 设置字体样式
              style: TextStyle(
                  //设置字体大小
                  fontSize: 20.0,
                  //字体颜色
                  color: Color.fromARGB(255, 255, 0, 0),
                  //添加下划线
                  decoration: TextDecoration.underline,
                  //下划线颜色
                  decorationColor: Color.fromARGB(200, 100, 255, 20),
                  //下划线样式
                  decorationStyle: TextDecorationStyle.solid),
            ),
          ),
        ));
  }
}