Flutter PDF编辑插件pdfeditor的使用

PDFEditor

开始使用

首先，在 pubspec.yaml 文件中添加 pdfeditor 包作为依赖。

dependencies:
  pdfeditor: ^x.x.x

然后，导入必要的包：

import 'package:pdfeditor/pdf_editor_view.dart';
import 'package:pdfeditor/pdf_view_controller.dart';

接下来，通过 PDFEditorView 来展示 PDF 文件：

late PDFViewController pdfViewController;

PDFEditorView(
  urlFile: "https://pspdfkit.com/downloads/pspdfkit-flutter-quickstart-guide.pdf",
  autoScales: true,
  onViewCreated: (controller) {
    pdfViewController = controller;
  },
  onError: (error) async {
    print(error.message);
  }
)

通过 pdfViewController 可以执行一些操作，例如保存或清除文件：

await pdfViewController.onSave();
// 保存更改后的文件

await pdfViewController.onClear();
// 清除本地文件

还可以使用 PDFEditor.download 方法从服务器或 API 下载文件：

PDFEditor.download(
  url: urlServer,
  savePath: tempDir.path + fileName,
  onSuccess: (fileName) {
    print('✅ File has finished downloading. Try opening the file.');
  },
  onFailed: (e) async {
    print(e.message);
  },
  onProgress: (progress) {
    print('Download progress: ${progress.toStringAsFixed(0)}% done.');
  }
);

示例代码

以下是完整的示例代码，展示了如何下载和打开 PDF 文件：

import 'dart:io';
import 'package:flutter/material.dart';
import 'package:flutter_platform_alert/flutter_platform_alert.dart';
import 'package:get/get.dart';
import 'package:path_provider/path_provider.dart';
import 'package:pdfeditor/pdf_editor.dart';
import 'rander_pdf_view.dart';

// PDF 文件名
const fileName = '/pspdfkit-flutter-quickstart-guide.pdf';

// PDF 文件的 URL
const urlServer = 'https://pspdfkit.com/downloads$fileName';

// PDF 图标的 URL
const pdfIconFile = "https://play-lh.googleusercontent.com/kIwlXqs28otssKK_9AKwdkB6gouex_U2WmtLshTACnwIJuvOqVvJEzewpzuYBXwXQQ";

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

class MyApp extends StatefulWidget {
  const MyApp({Key? key}) : super(key: key);

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

class _MyAppState extends State<MyApp> {
  String progressString = '文件尚未下载。';
  double progress = 0;
  bool didDownloadPDF = false;
  var file = '';
  late Directory tempDir;

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

  [@override](/user/override)
  Widget build(BuildContext context) {
    return GetMaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: const Text('PDFEditorView'),
        ),
        body: Builder(
          builder: (context) => Center(
            child: Column(
              mainAxisAlignment: MainAxisAlignment.center,
              children: [
                Image.network(
                  pdfIconFile,
                  width: 150,
                ),
                const SizedBox(
                  height: 50,
                ),
                const Text(
                  '首先，下载一个 PDF 文件。然后打开它。',
                ),
                TextButton(
                  style: TextButton.styleFrom(tapTargetSize: MaterialTapTargetSize.shrinkWrap),
                  onPressed: didDownloadPDF
                      ? null
                      : () async {
                    PDFEditor.download(
                      url: urlServer,
                      savePath: tempDir.path + fileName,
                      onSuccess: (fileName) {
                        setState(() {
                          print('✅ 文件已下载完成。尝试打开文件。');
                          didDownloadPDF = true;
                          Get.to(() => const RanderPDFView(), arguments: fileName);
                        });
                      },
                      onFailed: (e) async {
                        await FlutterPlatformAlert.showAlert(
                          windowTitle: 'PDFEditor 错误！',
                          text: e,
                          alertStyle: AlertButtonStyle.ok,
                          iconStyle: IconStyle.information,
                        );
                      },
                      onProgress: (progress) {
                        setState(() {
                          progressString = '下载进度: ${progress.toStringAsFixed(0)}% 完成。';
                        });
                      },
                    );
                  },
                  child: const Text('下载一个 PDF 文件'),
                ),
                Text(
                  progressString,
                ),
                TextButton(
                  style: TextButton.styleFrom(tapTargetSize: MaterialTapTargetSize.shrinkWrap),
                  onPressed: !didDownloadPDF
                      ? null
                      : () async {
                    Get.to(() => const RanderPDFView(), arguments: tempDir.path + fileName);
                  },
                  child: const Text('使用 PDFEditor 打开已下载的文件'),
                ),
                TextButton(
                  style: TextButton.styleFrom(tapTargetSize: MaterialTapTargetSize.shrinkWrap),
                  onPressed: !didDownloadPDF
                      ? null
                      : () async {
                    await File(tempDir.path + fileName).delete();
                    setState(() {
                      didDownloadPDF = false;
                      progressString = '文件尚未下载。';
                    });
                  },
                  child: const Text('清除临时 PDF 文件'),
                ),
                const Divider(),
                TextButton(
                  style: TextButton.styleFrom(tapTargetSize: MaterialTapTargetSize.shrinkWrap),
                  onPressed: () async {
                    Get.to(() => const RanderPDFView(), arguments: urlServer);
                  },
                  child: const Text('使用 PDFEditor 在线打开文件'),
                ),
              ],
            ),
          ),
        ),
      ),
    );
  }

  initdaDirectory() async {
    tempDir = await getTemporaryDirectory();
  }
}