如何将行号添加到Flutter上的TextField？

import 'package:flutter/material.dart';

class LineNumberTextField extends StatefulWidget {
  @override
  _LineNumberTextFieldState createState() => _LineNumberTextFieldState();
}

class _LineNumberTextFieldState extends State<LineNumberTextField> {
  TextEditingController _controller;
  List<int> _lineNumbers = [1];

  @override
  void initState() {
    super.initState();
    _controller = TextEditingController();
    _controller.addListener(_updateLineNumbers);
  }

  @override
  void dispose() {
    _controller.dispose();
    super.dispose();
  }

  void _updateLineNumbers() {
    String text = _controller.text;
    int lines = text.split('\n').length;

    setState(() {
      _lineNumbers = List.generate(lines, (index) => index + 1);
    });
  }

  @override
  Widget build(BuildContext context) {
    return Row(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        Column(
          children: _lineNumbers.map((lineNumber) {
            return Text(
              lineNumber.toString(),
              style: TextStyle(fontSize: 12),
            );
          }).toList(),
        ),
        SizedBox(width: 8),
        Expanded(
          child: ListView(
            shrinkWrap: true,
            physics: NeverScrollableScrollPhysics(),
            children: [
              TextField(
                controller: _controller,
                maxLines: null,
                decoration: InputDecoration(
                  border: OutlineInputBorder(),
                  hintText: 'Enter text here...',
                ),
              ),
            ],
          ),
        ),
      ],
    );
  }
}

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('Line Number TextField')),
        body: Padding(
          padding: EdgeInsets.all(16),
          child: LineNumberTextField(),
        ),
      ),
    );
  }
}