Why getUriForDownloadedFile() returns null

Question

I am downloading the picture via DownloadManager (API 28). The picture is successfully downloaded and displayed in ImageView. I want find out the file name. But getUriForDownloadedFile() return null. Why?

private void dowloadfile() {
    Uri uri = Uri.parse(editText.getText().toString());
    DownloadManager.Request request = new DownloadManager.Request(uri);
    request.setAllowedNetworkTypes(DownloadManager.Request.NETWORK_WIFI | DownloadManager.Request.NETWORK_MOBILE);
    request.setAllowedOverRoaming(false);
    request.setVisibleInDownloadsUi(true);
    request.setDestinationInExternalPublicDir(Environment.DIRECTORY_DOWNLOADS, "picture." + extension);

    registerReceiver(onComplete, new IntentFilter(DownloadManager.ACTION_DOWNLOAD_COMPLETE));

    refid = downloadManager.enqueue(request);
    Uri u = downloadManager.getUriForDownloadedFile(refid);
}

after enqueue, the download is a asyn operation, the uri might be assigned after the download has finished, you need to listen to your receiver and pass the id to get the uri — stallianz, Oct 24 '18 at 16:27
Thank you very much, you helped me a lot! I forgot about multithreading. — Aleksey, Oct 25 '18 at 06:03

score 1 · Accepted Answer · answered Oct 25 '18 at 09:32

1

after enqueue, the download is a asyn operation, the uri might be assigned after the download has finished, you need to listen to your receiver and pass the id to get the uri

answered Oct 25 '18 at 09:32

stallianz

176
1
17

How to add listener for the download has finished? – NickUnuchek Dec 10 '20 at 10:30
1

https://stackoverflow.com/questions/26210048/how-to-receive-status-of-download-manager-intent-until-download-success-or-faile – stallianz Dec 10 '20 at 23:28

Why getUriForDownloadedFile() returns null

1 Answers1