AsyncTask not passing progress (what does super.onprogressupdate do?)

I am using AsyncTask to download different mp3's from webview. When I track my download progress and pass to onprogress update, it receives a 0 no matter what I do. I have tried using Doubles, Floats, and Integers.. here is an example of my code:

public class DownloadFile extends AsyncTask<Void, Float, String> {                       

ProgressBar progressBar;
NotificationManager notificationManager;
Notification notification2;            

@Override
protected void onPreExecute() {                
    // configure the intent
    Intent intent = new Intent();
    final PendingIntent pendingIntent = PendingIntent.getActivity(getApplicationContext(), 0, intent, 0);

    // configure the notification
    notification2 = new Notification(R.drawable.download, "DOWNLOADING: " + filename3, System
            .currentTimeMillis());
    notification2.flags = notification2.flags | Notification.FLAG_ONGOING_EVENT;
    notification2.contentView = new RemoteViews(getApplicationContext().getPackageName(), R.layout.download_progress);
    notification2.contentIntent = pendingIntent;
    notification2.contentView.setTextViewText(R.id.percentage,"hi" );
    notification2.contentView.setTextViewText(R.id.status_text, "DOWNLOADING: " + filename3);
    notification2.contentView.setProgressBar(R.id.status_progress, 100, 0, false);

    getApplicationContext();
    notificationManager = (NotificationManager) getApplicationContext().getSystemService(
            Context.NOTIFICATION_SERVICE);

    notificationManager.notify(2, notification2);
}

@Override
protected String doInBackground(Void... params) {        
    try {

        //set the download URL, a url that points to a file on the internet
        //this is the file to be downloaded
        URL url = songURL2;


        //create the new connection
        HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();

        //set up some things on the connection
        urlConnection.setRequestMethod("GET");
        urlConnection.setDoOutput(true);

        //and connect!
        urlConnection.connect();

        //set the path where we want to save the file
        //in this case, going to save it on the root directory of the
        //sd card.
        SDCardRoot = Environment.getExternalStorageDirectory() + "/download/";
        //create a new file, specifying the path, and the filename
        //which we want to save the file as.
        File file = new File(SDCardRoot,filename3);

        //this will be used to write the downloaded data into the file we created
        FileOutputStream fileOutput = new FileOutputStream(file);

        //this will be used in reading the data from the internet
        InputStream inputStream = urlConnection.getInputStream();

        //this is the total size of the file
        Integer totalSize = urlConnection.getContentLength();
        //variable to store total downloaded bytes
        float downloadedSize = 0;

        //create a buffer...
        byte[] buffer = new 开发者_运维问答byte[1024];
        int bufferLength = 0; //used to store a temporary size of the buffer

        //now, read through the input buffer and write the contents to the file
        while ( (bufferLength = inputStream.read(buffer)) > 0 ) {
                //add the data in the buffer to the file in the file output stream (the     file on the sd card
                fileOutput.write(buffer, 0, bufferLength);
                //add up the size so we know how much is downloaded
                downloadedSize += bufferLength;
                //this is where you would do something to report the prgress, like this maybe


                publishProgress((downloadedSize * 100)/totalSize) * 100);


        }
        //close the output stream when done
        fileOutput.close();

       return "Success";



//catch some possible errors...
} catch (MalformedURLException e) {             
        e.printStackTrace();
    return "Failed";
} catch (IOException e) {               
        e.printStackTrace();
           return "Failed";
}
}               

protected void onProgressUpdate(Float... progress) {

    notification2.contentView.setProgressBar(R.id.status_progress, 100, (int)progress[0], false);
    String stringy = progress + "%";
    TextView textytext = (TextView) findViewById(R.id.percentage);
    textytext.setText(stringy);
    notificationManager.notify(2, notification2);           
}

@Override
protected void onPostExecute(String result) {

    notificationManager.cancel(2);          
}
}       

I was struggling with this all day yesterday and throughout the night. Does super.onprogressupdate() have anything to do with this case, and anyone know a solution? I am pulling my hair out.

EDIT: Oh and I am trying to use it so I can publish this progress to the progress bar I have in my custom notification, but you can probably tell that by the code.

EDIT #2: So I have been doing some testing and I changed my progress to the right arithmetic which is

myProgress = (downloadedSize/totalSize) * 100;

then I said if myProgress > 50 then publishProgress(50);

by doing this the progress bar jumps to 50 when the download is half way done. then I slip my variable and it doesn't pass the variables data to onProgressUpdated.

Does anyone know why a hard-coded number is working but not a number in a variable??

Log, log, log! Log the heck out of this sort of situation and see what your inputs, outputs, and intermediate values are all working out to at any given moment. (Or use breakpoints in the debugger, but that's another more complicated story).

Are you sure getContentLength() is returning what you think it's returning? Also, you're multiplying your done / total value by 100 twice, so check your math there, too. Try inserting a few logging statements and make sure you're actually sending the values you think you're sending to publishProgress. (eg. try just putting publishProgress(94.0) instead, just on a lark). I suspect the problem is something to do with the contentlength not being reported by the server or your arithmetic being off -- or possibly with the data being small enough that you don't actually see the intermediate value (most of the time on wifi/3G is spent establishing the connection and waiting on latency; the actual data transfer portion is usually quite fast, especially for smaller files).

So I have been doing a lot of testing and I have gotten it to work flawlessly with the Android Emulator, what I did was say

 if (myProgress is > 1) && (myProgress > previousProgress) {
previousProgress = myProgress
publishProgress(myProgress);}

The weird thing is that in the emulator it works perfect every time, but using my phone the progressbar doesn't progress. At first it did once or twice and now it doesn't for any song. Whereas the emulator progresses for any song. Why would this work on the emulator and not a real phone?

Sound like a java problem to me, I am new to java myself. I recently discovered in java, when divide integer types you will always get a int value, no matter what. try declare totalSize as float or (float) convert it to float when doing division

also I noticed

publishProgress((downloadedSize * 100)/totalSize) * 100);

Looks odd, maybe you tried some hack to make code work, shouldn't it be downloadedSize/totalSize*100 ?

use publishProgress((downloadedSize * 100) /totalSize) );
reason of getting Zero every time is because of dividing the downloadedSize by totalSize rounds up the result to Zero and hence you the reult is always zero.