在Flutter中添加新文本行的问题

import 'package:flutter/material.dart';

class MyWidget extends StatefulWidget {
  @override
  _MyWidgetState createState() => _MyWidgetState();
}

class _MyWidgetState extends State<MyWidget> {
  List<String> textLines = ['Line 1', 'Line 2', 'Line 3'];

  void addNewLine() {
    setState(() {
      textLines.add('New Line');
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Dynamic Text Lines'),
      ),
      body: ListView.builder(
        itemCount: textLines.length,
        itemBuilder: (context, index) {
          return ListTile(
            title: Text(textLines[index]),
          );
        },
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: addNewLine,
        child: Icon(Icons.add),
      ),
    );
  }
}

void main() {
  runApp(MaterialApp(
    home: MyWidget(),
  ));
}