Android DownloadManager API - opening file after download?

I am facing problem of opening downloaded file after successfull download via DownloadManager API. In my code:

Uri uri=Uri.parse("http://www.nasa.gov/images/content/206402main_jsc2007e113280_hires.jpg");

Environment
    .getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS)
    .mkdirs();

lastDownload = mgr.enqueue(new DownloadManager.Request(uri)
    .setAllowedNetworkTypes(DownloadManager.Request.NETWORK_WIFI |
                            DownloadManager.Request.NETWORK_MOBILE)
    .setAllowedOverRoaming(false)
    .setTitle("app update")
    .setDescription("New version 1.1")
    .setShowRunningNotification(true)
    .setDestinationInExternalPublicDir(Environment.DIRECTORY_DOWNLOADS, "a.apk"));

Cursor c=mgr.query(new DownloadManager.Query().setFilterById(lastDownload));

if(c.getInt(c.getColumnIndex(DownloadManager.COLUMN_STATUS)) == 8) {
    try {
        mgr.openDownloadedFile(c.getLong(c.getColumnIndex(DownloadManager.COLUMN_ID)));
    } catch (NumberFormatException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
        Log.d("MGR", "Error");
    } catch (FileNotFoundException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
        Log.d("MGR", "Error");
    }
}

Problem is when is if(c.getInt(c.getColumnIndex(DownloadManager.COLUMN_STATUS))==8) evoked. I got status -1 and an exception. Is there any better way, how to open downloaded files with DownloadManager API? In my example I am downloading a big image, in a real situation I would be downloading an APK file and I need to display an installation dialog immediately after udpate.

Edit: I figured out that status=8 is after successfull download. You might have different "checking successfull download" approach

Thanks

Solution

You need to register a reciever for when the download is complete:

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

and a BroadcastReciever handler

BroadcastReceiver onComplete=new BroadcastReceiver() {
    public void onReceive(Context ctxt, Intent intent) {
        // Do Something
    }
};

Buy instead of me ripping off everything, I suggest you'll check this out.

EDIT:

Just as a suggestion, I wouldn't recommend using API 9 just yet: http://developer.android.com/resources/dashboard/platform-versions.html

There are ways around this, by creating your very own download handler, like I did, because we didn't want to alienate most of our android's user base, for that you'll need: Create AsyncTask which handles the file download.

and i'll recommend to create a download dialog of some sort (if you say it's a big file, i'd make it appear in the notification area).

and than you'll need to handle the opening of the file:

protected void openFile(String fileName) {
    Intent install = new Intent(Intent.ACTION_VIEW);
    install.setDataAndType(Uri.fromFile(new File(fileName)),
            "MIME-TYPE");
    startActivity(install);
}