Flutter web从API下载pdf并保存在目录中

import 'dart:io';
import 'package:flutter/material.dart';
import 'package:http/http.dart' as http;
import 'package:path_provider/path_provider.dart';
import 'package:dio/dio.dart';

class DownloadPDFScreen extends StatefulWidget {
  @override
  _DownloadPDFScreenState createState() => _DownloadPDFScreenState();
}

class _DownloadPDFScreenState extends State<DownloadPDFScreen> {
  bool _downloading = false;

  Future<void> _downloadPDF() async {
    setState(() {
      _downloading = true;
    });

    try {
      // 发送HTTP请求获取API响应数据
      final response = await http.get('API的URL');

      // 获取设备上的临时目录路径
      final directory = await getTemporaryDirectory();
      final filePath = '${directory.path}/example.pdf';

      // 使用dio下载PDF文件并保存到目录中
      final dio = Dio();
      await dio.download(response.bodyBytes, filePath);

      setState(() {
        _downloading = false;
      });

      print('PDF下载完成，保存路径：$filePath');
    } catch (e) {
      setState(() {
        _downloading = false;
      });

      print('下载PDF时出现错误：$e');
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('下载PDF'),
      ),
      body: Center(
        child: _downloading
            ? CircularProgressIndicator()
            : RaisedButton(
                child: Text('下载PDF'),
                onPressed: _downloadPDF,
              ),
      ),
    );
  }
}