protected Void doInBackground(Void... params) {
      String outString;
      HttpURLConnection c = null;
      DataOutputStream os = null;

      outString = scanData.getOwnBSSID();
      outString = outString + "\nL\tX\t" + lastLat + "\t" + lastLon + "\n";

      try {
        URL connectURL = new URL("http://www.openwlanmap.org/android/upload.php");
        c = (HttpURLConnection) connectURL.openConnection();
        if (c == null) {
          return null;
        }

        c.setDoOutput(true); // enable POST
        c.setRequestMethod("POST");
        c.addRequestProperty("Content-Type", "application/x-www-form-urlencoded, *.*");
        c.addRequestProperty("Content-Length", "" + outString.length());
        os = new DataOutputStream(c.getOutputStream());
        os.write(outString.getBytes());
        os.flush();
        c.getResponseCode();
        os.close();
        outString = null;
        os = null;
      } catch (IOException ioe) {
      } finally {
        try {
          if (os != null) os.close();
          if (c != null) c.disconnect();
        } catch (IOException ioe) {
          ioe.printStackTrace();
        }
      }
      return null;
    }
    protected Boolean doInBackground(ArrayList... params) {
      download_photos.this.runOnUiThread(
          new Runnable() {
            public void run() {
              mtext.setText(
                  getText(R.string.download_textview_message_1) + " " + path.toString() + ". ");
            }
          });

      if (resume_file.exists()) {
        initial_value = readProgress()[0];
      } else {
        initial_value = 1;
      }

      for (int i = initial_value - 1; i < links.size(); i++) {
        // asynctask expects more than one ArrayList<String> item, but we are sending only one,
        // which is params[0]
        Uri imageuri = Uri.parse(params[0].get(i).toString());
        URL imageurl = null;
        HttpURLConnection connection = null;
        total_files_to_download = links.size();
        completed_downloads = i + 1;
        try {
          imageurl = new URL(params[0].get(i).toString());
          connection = (HttpURLConnection) imageurl.openConnection();
          connection.connect();
        } catch (Exception e) {
          // TODO Auto-generated catch block
          e.printStackTrace();
        }

        // extracts the real file name of the photo from url
        path_segments = imageuri.getPathSegments();
        int total_segments = path_segments.size();
        file_name = path_segments.get(total_segments - 1);

        path.mkdirs();

        // if(i==0)
        //	first_image = path.toString() + "/" + file_name;

        InputStream input;
        OutputStream output;
        try {
          input = new BufferedInputStream(imageurl.openStream());
          fully_qualified_file_name = new File(path, file_name);
          output = new BufferedOutputStream(new FileOutputStream(fully_qualified_file_name));
          byte data[] = new byte[1024];
          int count;
          while ((count = input.read(data)) != -1) {
            output.write(data, 0, count);
          }
          output.flush();
          output.close();
          input.close();
          connection.disconnect();

          new folder_scanner(getApplicationContext(), fully_qualified_file_name);

          publishProgress(completed_downloads, total_files_to_download);
          if (this.isCancelled()) {
            writeProgress(completed_downloads, total_files_to_download);
            break;
          }

        } catch (IOException e) {
          // TODO Auto-generated catch block
          e.printStackTrace();
        }

        // creates required folders and subfolders if they do not exist already
        // boolean success = path.mkdirs();

        // makes request to download photos
        // DownloadManager.Request request = new DownloadManager.Request(imageuri);

        // set path for downloads
        // request.setDestinationInExternalPublicDir(Environment.DIRECTORY_PICTURES,sub_path);

        // request.setDescription("Downloaded using Facebook Album Downloader");

        // DownloadManager dm = (DownloadManager)getSystemService(DOWNLOAD_SERVICE);

        // download is enqueue in download list. it returns unique id for each download
        // download_id = dm.enqueue(request);

      }
      // returns the unique id. we are not using this id
      return true;
    }