How to download Muliple files (image/video url) by DownloadManager in Android

Question

Download Manager is the best way to download single file in android, It maintain Notification bar also.but how i can download Multiple files by it and show the whole downloading status by progressing bar in Notification.

Please suggest any library for it or any code snippet.

Answer 1

You can probably hide the DownloadManager's notification and show your own, that should do what you want.

To disable setNotificationVisibility(DownloadManger.VISIBILITY_HIDDEN); to hide the notification.

To show download progress, you can register a ContentObserver on DownloadManager's database to get periodic updates and update your own notification with it.

Cursor mDownloadManagerCursor = mDownloadManager.query(new DownloadManager.Query());
if (mDownloadManagerCursor != null) {
    mDownloadManagerCursor.registerContentObserver(mDownloadFileObserver);
}

And the ContentObserver will look something like:

private ContentObserver mDownloadFileObserver = new ContentObserver(new Handler(Looper.getMainLooper())) {
    @Override
    public void onChange(boolean selfChange) {
        Cursor cursor = mDownloadManager.query(new DownloadManager.Query());

        if (cursor != null) {
            long bytesDownloaded = 0;
            long totalBytes = 0;

            while (cursor.moveToNext()) {
                bytesDownloaded += cursor.getLong(cursor.getColumnIndex(DownloadManager.COLUMN_BYTES_DOWNLOADED_SO_FAR));
                totalBytes += cursor.getLong(cursor.getColumnIndex(DownloadManager.COLUMN_TOTAL_SIZE_BYTES));
            }

            float progress = (float) (bytesDownloaded * 1.0 / totalBytes);
            showNotificationWithProgress(progress);

            cursor.close();
        }
    }
};

And the notification with progress can be shown with:

public void showNotificationWithProgress(Context context, int progress) {
    NotificationManagerCompat.from(context).notify(0,
            new NotificationCompat.Builder(context)
                    .setSmallIcon(R.mipmap.ic_launcher)
                    .setContentTitle("Downloading...")
                    .setContentText("Progress")
                    .setProgress(100, progress * 100, false)
                    .setOnGoing(true)
                    .build());
}