总是使用flutter下载器包下载失败

Question

我尝试使用 flutter 下载器包从 firebase 存储下载 pdf 文件。但是下载总是显示失败，不知道是什么原因。

这是我试过的代码。请提出一些解决方案。提前致谢。

void _startDownload(String link) async
{
   var dir = await getExternalStorageDirectory();
   try{
      final taskId = await FlutterDownloader.enqueue(
      url: link,
      savedDir:  dir.path,
      fileName:"sampe.docx",
      showNotification: true, // show download progress in status bar(forAndroid)
      openFileFromNotification: true, // click on notification to open downloaded file (for Android)
      );
      debugPrint(taskId);

   //   FlutterDownloader.retry(taskId: taskId);
  }
  catch(e){
     print(e);
  }
}

这是我收到的错误。

W/System.err(18012): java.io.FileNotFoundException: /storage/emulated/0/sampe.docx (Permission denied)
W/System.err(18012):    at java.io.FileOutputStream.open(Native Method)
W/System.err(18012):    at java.io.FileOutputStream.<init>(FileOutputStream.java:221)
W/System.err(18012):    at java.io.FileOutputStream.<init>(FileOutputStream.java:140)
W/System.err(18012):    at vn.hunghd.flutterdownloader.DownloadWorker.downloadFile(DownloadWorker.java:190)
W/System.err(18012):    at vn.hunghd.flutterdownloader.DownloadWorker.doWork(DownloadWorker.java:102)
W/System.err(18012):    at androidx.work.Worker$1.run(Worker.java:57)
W/System.err(18012):    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1133)
W/System.err(18012):    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:607)
W/System.err(18012):    at java.lang.Thread.run(Thread.java:760)
I/WorkerWrapper(18012): Worker result SUCCESS for Work [ id=b7676538-a655-454a-89e2-1899f0e078cd, tags={ vn.hunghd.flutterdownloader.DownloadWorker, flutter_download_task } ]

Answer 1

确保您有写权限。没有读、写权限

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>