如何在Flutter中使用TextFromField上的按键事件？

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('TextField Key Event Example')),
        body: MyHomePage(),
      ),
    );
  }
}

class MyHomePage extends StatefulWidget {
  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  FocusNode _focusNode = FocusNode();

  @override
  void initState() {
    super.initState();
    _focusNode.addListener(() {
      if (_focusNode.hasFocus) {
        print('TextField has focus');
      } else {
        print('TextField lost focus');
      }
    });
  }

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

  void _handleKeyEvent(RawKeyEvent event) {
    if (event is RawKeyDownEvent) {
      print('Key pressed: ${event.logicalKey}');
      // 根据需要处理按键事件
      if (event.logicalKey == LogicalKeyboardKey.enter) {
        print('Enter key was pressed');
        // 执行你的操作，例如提交表单
      }
    }
  }

  @override
  Widget build(BuildContext context) {
    return RawKeyboardListener(
      focusNode: _focusNode,
      onKey: _handleKeyEvent,
      child: TextField(
        decoration: InputDecoration(
          labelText: 'Enter text',
        ),
      ),
    );
  }
}