Showing progress bar until the download completes - Android

Question

I am using the following code to download a video from the website.The download function is working fine and I have a small problem with the progress bar. The progress bar remains the same and does not update itself with increasing values.

@Override
protected Dialog onCreateDialog(int id) {
    switch (id) {
        case progress_bar_type: // we set this to 0
            pDialog = new ProgressDialog(this);
            pDialog.setMessage("Downloading file. Please wait...");
            pDialog.setIndeterminate(false);
            pDialog.setMax(100);
            pDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
            pDialog.setCancelable(true);
            pDialog.show();
            return pDialog;
        default:
            return null;
    }
}

class DownloadFile1 extends AsyncTask<String, Integer, String> {
    ProgressDialog bar;
    public String videoToDownload;
    public String fileName;

    /**
     * Before starting background thread
     * Show Progress Bar Dialog
     */
    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        showDialog(progress_bar_type);
    }

    @Override
    protected String doInBackground(String... params) {
        int count;

        try {
            mp4load(videoToDownload);
        } catch (Exception e) {
            // TODO: handle exception
        }

        return null;
    }

    public void mp4load(String urling) {
        try {
            System.out.println("Downloading");
            URL url = new URL(urling);
            HttpURLConnection con = (HttpURLConnection) url.openConnection();
            con.setRequestMethod("GET");
            //c.setDoOutput(true);
            con.connect();

            // String downloadsPath = Environment.getExternalStoragePublicDirectory();
            File SDCardRoot = Environment.getExternalStorageDirectory();

            File outputFile = new File(SDCardRoot, fileName);

            if (!outputFile.exists()) {
                outputFile.createNewFile();
            }

            FileOutputStream fos = new FileOutputStream(outputFile);

            int status = con.getResponseCode();

            InputStream is = con.getInputStream();

            byte[] buffer = new byte[1024];
            int len1 = 0;
            while ((len1 = is.read(buffer)) != -1) {
                fos.write(buffer, 0, len1);
            }
            fos.close();
            is.close();
            System.out.println("Downloaded");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    /**
     * Updating progress bar
     */
    protected void onProgressUpdate(String... progress) {
        // setting progress percentage
        pDialog.setProgress(Integer.parseInt(progress[0]));
    }

    /**
     * After completing background task
     * Dismiss the progress dialog
     **/
    @Override
    protected void onPostExecute(String file_url) {
        // dismiss the dialog after the file was downloaded
        dismissDialog(progress_bar_type);
    }
}

The progress bar remains exactly at 0% progress and disappears after the download is completed. How to change the updating part of the progress bar?

Answer 1

Referring to the AsyncTask Docs, your progress type argument has to be integer, as your AsyncTask class is declared as follows.

class DownloadFile1 extends AsyncTask<String, Integer, String> {

Therefore, change the

public void onProgressUpdate(String..Progress)

to public void onProgressUpdate(Integer..Progress)

and then use the override annotation

Answer 2

Inside your doInBackground call the publishProgress method passing an Integer to be set in the progress bar.

protected String doInBackground(String... params) {
    int count;

    try {
        mp4load(videoToDownload);
    } catch (Exception e) {
        // TODO: handle exception
    }

    return null;
}

You'll need to move the code form your method mp4load to the doInBackground in order to modify the code like this:

System.out.println("Downloading");
            URL url = new URL(urling);
            HttpURLConnection con = (HttpURLConnection) url.openConnection();
            con.setRequestMethod("GET");
            //c.setDoOutput(true);
            con.connect();

            // String downloadsPath = Environment.getExternalStoragePublicDirectory();
            File SDCardRoot = Environment.getExternalStorageDirectory();

            File outputFile = new File(SDCardRoot, fileName);

            if (!outputFile.exists()) {
                outputFile.createNewFile();
            }

            FileOutputStream fos = new FileOutputStream(outputFile);

            int status = con.getResponseCode();

            InputStream is = con.getInputStream();
            int fileLength = con.getContentLength();
            long total = 0;
            byte[] buffer = new byte[1024];
            int len1 = 0;
            while ((len1 = is.read(buffer)) != -1) {
                fos.write(buffer, 0, len1);
                total += len1;
                publishProgress((int) (total * 100 / fileLength));
            }
            fos.close();
            is.close();

The idea is simple, you need to get the size of the file and slowly update the progressbar with as you download the file.