Android: Download file octet-stream web view

Question

I want to be able to download a file through Android's webview but I cannot do it.

The url I have to download from is in this format:

http://{server_path}/Download?mimetype=application/octet-stream

I am using this code:

myWebView.setDownloadListener(new DownloadListener() {
  public void onDownloadStart(String url, String userAgent,
                              String contentDisposition, String mimetype,
                              long contentLength) {
    DownloadManager.Request request = new DownloadManager.Request(Uri.parse(url));

    request.setMimeType(mimetype);
    //------------------------COOKIE!!------------------------
    String cookies = CookieManager.getInstance().getCookie(url);
    request.addRequestHeader("cookie", cookies);
    //------------------------COOKIE!!------------------------
    request.addRequestHeader("User-Agent", userAgent);
    request.setDescription("Downloading file...");
    request.setTitle(URLUtil.guessFileName(url, contentDisposition, mimetype));
    request.allowScanningByMediaScanner();
    request.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED);
    request.setDestinationInExternalPublicDir(Environment.DIRECTORY_DOWNLOADS, URLUtil.guessFileName(url, contentDisposition, mimetype));
    DownloadManager dm = (DownloadManager) getSystemService(DOWNLOAD_SERVICE);
    long donwloadedFileId = dm.enqueue(request);
    String downloadedMimeType = dm.getMimeTypeForDownloadedFile(donwloadedFileId)
    Toast.makeText(getApplicationContext(), "Downloading File", Toast.LENGTH_LONG).show();
  }
});

When I try to download all I get is a "download.bin" file.

As I check the function URLUtil.guessFileName(url, contentDisposition, mimetype) returns this as a file name.

Could you help me?

EDIT

If I rename the downloaded file from Android File manager app, it opens succefully. So maybe the answer is how can I set the correctly mimeType of the downloaded file?

EDIT 2 (13/4/20)

Also I forgot to mention that in the above code mimeType is "application/octet-stream"

score 1 · Answer 1 · answered Apr 08 '20 at 13:14

@Net Here is the debug output:

this = {MainActivity$1@10423} 
url = "http://{server_path}/Download?mimetype=application/octet-stream"
userAgent = "Mozilla/5.0 (Linux; Android 10; Android SDK built for x86 Build/QSR1.191030.002; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/74.0.3729.185 Mobile Safari/537.36"
contentDisposition = "attachment; filename*=UTF-8''M1FBACTFMB9F.pdf"
mimetype = "application/octet-stream"
contentLength = 192748
request = {DownloadManager$Request@10430} 
dm = {DownloadManager@10432}

Thanks @christos , i have added mimetype = "application/octet-stream" and now able to download and view — varotariya vajsi, Apr 07 '22 at 14:33

Ner · Answer 2 · 2020-04-08T13:27:14.207

0

You can try to do this with your file:

File file = new File(yourFileHere);
mimeType= URLConnection.guessContentTypeFromName(file.getName());

or try

Files.probeContentType(path)

EDIT

Add the next header to your request:

"content-disposition", "attachment; filename=\"" + fileName +"\""

edited Apr 08 '20 at 13:27

answered Apr 08 '20 at 11:24

Ner

104
6

The output result is also "application/octet-stream" – Christos Boutsikas Apr 08 '20 at 12:19
What is the extension of the file that you receive in the url? application/octet-stream meaning “download this file” – Ner Apr 08 '20 at 12:58
below is my debug output – Christos Boutsikas Apr 08 '20 at 13:51
I don't know if I misunderstood, but it's not working again. I added this : `request.addRequestHeader("content-disposition", contentDisposition);` – Christos Boutsikas Apr 10 '20 at 14:40
check this post https://stackoverflow.com/questions/3028306/download-a-file-with-android-and-showing-the-progress-in-a-progressdialog?rq=1 – Ner Apr 14 '20 at 08:19

Android: Download file octet-stream web view

2 Answers2