Android中的下载管理器

Question

I'm developing a magazine app and I need to download one edition of the magazine to be available in offline mode. One edition may have 20 articles.

I'm using download manager to download the articles, enqueueing all of them, but I need a callback when finished to download all articles of one edition.

If I click to download two magazines at once, it'll enqueue all the articles of both magazines and I need that they be individual.

So far I have this:

mDownloadManager = (DownloadManager) getSystemService(Context.DOWNLOAD_SERVICE);
for (final Materia materia : materiasList) {
    String url = materia.url;
    DownloadManager.Request request = new DownloadManager.Request(Uri.parse(url));
    request.setDescription("Baixando...");
    request.setTitle(mEditionTitle + " - " + materia.titulo);
    request.allowScanningByMediaScanner();
    request.setDestinationInExternalFilesDir(mContext, "/editions/" + String.valueOf(mEditionId) + File.separator, String.valueOf(materia.id) + ".html");
    // get download service and enqueue file
    mDownloadManager.enqueue(request);
}

EDIT: I'm running this manager from a service.

Answer 1

Not sure this is the best solution but you could query your download manager at regular interval and get all the in progress downloads. Then you parse the result and check if it is still downloading some items for a collection or if they are all downloaded.

Query the manager:

ArrayList<QueuedDownload> downloads = new ArrayList<>();
DownloadManager downloadManager = (DownloadManager) context.getSystemService(Context.DOWNLOAD_SERVICE);
DownloadManager.Query myDownloadQuery = new DownloadManager.Query();
myDownloadQuery.setFilterByStatus(DownloadManager.STATUS_RUNNING | DownloadManager.STATUS_PAUSED | DownloadManager.STATUS_PENDING);
Cursor cursor = downloadManager.query(myDownloadQuery);
while (cursor.moveToNext()) {
    // Parse each download
}
cursor.close();

Of course that should run on a background thread.