Flutter HWP文件处理插件flutter_hwp_lib的使用

1. 简介

本项目旨在从由Hancom公司开发的Hangul程序创建的HWP文件中提取文本，并通过利用名为hwplib的Java库将其在Flutter中使用。

• 该项目基于hwplib提供的示例编写了用于提取文本的API。
• 在使用示例时，我们使用了file_picker库作为依赖项。

2. 截图

Home	Select File	MethodChannel Call	EventChannel Call

3. 使用

import 'package:flutter_hwp_lib/flutter_hwp_lib.dart';

// 插件实例
final _flutterHwpLibPlugin = FlutterHwpLib();

// 提取文本
var filePath = 'file path';
var text = await _flutterHwpLibPlugin.extractingText(filePath);

// 处理大文件
var filePath = 'file path';
await _flutterHwpLibPlugin.extractingTextFromBigFile(filePath).listen((event) {
  // 事件处理器
});

完整示例代码

以下是一个完整的示例代码，展示了如何使用flutter_hwp_lib插件来处理HWP文件：

import 'package:file_picker/file_picker.dart';
import 'package:flutter/material.dart';
import 'dart:async';
import 'package:flutter/services.dart';
import 'package:flutter_hwp_lib/flutter_hwp_lib.dart';

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

class MyApp extends StatefulWidget {
  const MyApp({super.key});

  [@override](/user/override)
  State<MyApp> createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  String _platformVersion = 'Unknown';
  final _flutterHwpLibPlugin = FlutterHwpLib();

  List<String> _events = [];
  final _eventStreamController = StreamController<String>();
  final ScrollController _scrollController = ScrollController();

  [@override](/user/override)
  void initState() {
    super.initState();
    initPlatformState();
  }

  [@override](/user/override)
  void dispose() {
    _eventStreamController.close();
    super.dispose();
  }

  // 平台消息是异步的，因此我们在异步方法中初始化
  Future<void> initPlatformState() async {
    String platformVersion;
    // 平台消息可能会失败，所以我们使用try/catch处理PlatformException。
    // 我们还处理消息可能返回null的情况。
    try {
      platformVersion = await _flutterHwpLibPlugin.getPlatformVersion() ?? '未知平台版本';
    } on PlatformException {
      platformVersion = '获取平台版本失败。';
    }

    // 如果小部件在异步平台消息仍在飞行时被从树中移除，我们希望丢弃回复而不是调用setState以更新我们的不存在的外观。
    if (!mounted) return;

    setState(() {
      _platformVersion = platformVersion;
    });
  }

  [@override](/user/override)
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: const Text(
            'flutter_hwp_lib 示例',
            style: TextStyle(fontSize: 27, fontWeight: FontWeight.bold),
          ),
        ),
        body: Padding(
          padding: EdgeInsets.symmetric(vertical: 10, horizontal: 10),
          child: Column(
            children: [
              SizedBox(height: 20),
              Column(
                children: [
                  Row(
                    mainAxisAlignment: MainAxisAlignment.spaceBetween,
                    children: [
                      Text(
                        'MethodChannel 调用',
                        style: TextStyle(fontSize: 20, fontWeight: FontWeight.bold),
                      ),
                      ElevatedButton(
                        onPressed: () async {
                          String? filePath = "";
                          String full_path = "";

                          FilePickerResult? result = await FilePicker.platform.pickFiles();
                          if (result != null) {
                            filePath = result.files.single.path;
                            full_path = filePath.toString();
                            if (filePath != null) {
                              print("----------------->filePath: " + filePath);
                              print("----------------->fullPath: " + full_path);
                              await _extractingText(filePath);
                            }
                          } else {
                            // 用户取消了选择器
                          }
                        },
                        child: Text("选择文件"),
                      ),
                    ],
                  ),
                ],
              ),
              SizedBox(height: 20),
              Column(
                children: [
                  Row(
                    mainAxisAlignment: MainAxisAlignment.spaceBetween,
                    children: [
                      Text(
                        'EventChannel 调用',
                        style: TextStyle(fontSize: 20, fontWeight: FontWeight.bold),
                      ),
                      ElevatedButton(
                        onPressed: () async {
                          String? filePath = "";
                          String full_path = "";

                          FilePickerResult? result = await FilePicker.platform.pickFiles();
                          if (result != null) {
                            filePath = result.files.single.path;
                            full_path = filePath.toString();
                            if (filePath != null) {
                              print("----------------->filePath: " + filePath);
                              print("----------------->fullPath: " + full_path);

                              _extractingTextFromBigFile(filePath);
                            }
                          } else {
                            // 用户取消了选择器
                          }
                        },
                        child: Text("选择文件"),
                      ),
                    ],
                  ),
                  SizedBox(height: 10),
                  Container(
                    child: Container(
                      width: double.infinity,
                      height: MediaQuery.of(context).size.height * 0.6,
                      decoration: BoxDecoration(
                        border: Border.all(color: Colors.grey),
                      ),
                      child: ListView.builder(
                        controller: _scrollController,
                        itemCount: _events.length,
                        itemBuilder: (context, index) {
                          return ListTile(
                            title: Text(
                              _events[index],
                              style: TextStyle(fontSize: 15),
                            ),
                          );
                        },
                      ),
                    ),
                  ),
                ],
              ),
            ],
          ),
        ),
      ),
    );
  }

  Future<void> _extractingText(String filePath) async {
    _clearLog();
    _eventStreamController.sink.add('MethodChannel 调用...');

    var text = await _flutterHwpLibPlugin.extractingText(filePath);
    _eventStreamController.sink.add('-> ' + text!);
    _addEvent('MethodChannel 调用...');
    _addEvent(text);
  }

  StreamSubscription<dynamic>? _eventSubscription;
  void _extractingTextFromBigFile(String filePath) async {
    _clearLog();
    _eventStreamController.sink.add('EventChannel 调用...');

    _addEvent('EventChannel 调用...');
    _eventSubscription = await _flutterHwpLibPlugin
        .extractingTextFromBigFile(filePath)
        .listen((event) {
      _eventStreamController.sink.add('-> ' + event);
      _addEvent(event);
      print('---------------------->event: ' + event);
    });
  }

  void _clearLog() {
    setState(() {
      _events.clear();
    });
  }

  void _addEvent(String event) {
    setState(() {
      _events.add(event);
    });

    // 滚动到列表的末尾
    _scrollController.jumpTo(_scrollController.position.maxScrollExtent);
  }
}