Android Asynctask get last progress in background after destroy activity

Issue

What I want to do now is loop download pdf from URL that has about 875 Files.

I have already done this by using Asynctask and update the progress in progress dialog also everything is working fine, but what I had a problem is when the user clicks on my DOWNLOAD IN BACKGROUND button, the download is still going on and then I want to re-open the activity again. but the progress and name of the file that displays to the user is not showing anymore.

I know that when we start new activity it will ignore the background running process of our last Asynctask, so how could we solve this problem? (sorry for my English, it's my first time through on StackOverflow)

my code is similar to this

Here sample of my code:

class DownloadFileFromURL extends AsyncTask<ArrayList<LawDocument>,Integer, String> {

    private boolean running = true;
    Exception error;

    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        if(haveNetworkConnection()){
            showDialog(progress_bar_type);
        }else {
            running = false;
            showdailog();
        }
    }

    @Override
    protected void onCancelled() {
        super.onCancelled();
        running = false;
    }

    @Override
    protected String doInBackground(ArrayList<LawDocument>[] f_url) {
        ArrayList<LawDocument> passed = f_url[0]; //get passed arraylist
        System.out.println("Data::" + passed.size());
        int count;

        InputStream input = null;
        OutputStream output = null;
        while(!isCancelled()) {
            try {

                for (int i = 0; i < passed.size(); i++) {

                        File file = getBaseContext().getFileStreamPath(passed.get(i).getActualFilename());
                          if (file.exists()){
                                countfile+=1;
                               pDialog.setMessage(" Exist / "+ConstantClass.filecount);
                          }else{
                        Log.d("checkFilecount" + i, "fileName: " + passed.get(i).getFileName());
                        String filename = passed.get(i).getFileName().substring(passed.get(i).getFileName().lastIndexOf("/") + 1);
                        Log.d("checkFile", "name: " + filename);
                        URL url = new URL(passed.get(i).getFileName());
                        System.out.println("Data::" + passed.get(i).getFileName());
                        URLConnection conection = url.openConnection();
                        conection.connect();
                        // getting file length
                        int lenghtOfFile = conection.getContentLength();
                        // input stream to read file - with 8k buffer
                        input = new BufferedInputStream(url.openStream(), 8192);
                        //input = new BufferedInputStream(url.openStream(), 20000);
                        System.out.println("Data::" + passed.get(i).getFileName());
                        System.out.println("Data::" + filename);
                        // Output stream to write file
                        output = new FileOutputStream(getApplicationContext().getFilesDir() + "/" + filename);

                        byte data[] = new byte[1024];

                        long total = 0;

                        while ((count = input.read(data)) != -1) {
                            total += count;
                            // publishing the progress....
                            // After this onProgressUpdate will be called
                            publishProgress((int) ((total * 100) / lenghtOfFile));

                            // writing data to file
                            output.write(data, 0, count);
                        }
                        countfile+=1;
                        runOnUiThread(new Runnable() {
                            @Override
                            public void run() {
                                pDialog.setMessage(countfile+" / "+ConstantClass.filecount);
                            }
                        });
                    }


                }
            } catch (Throwable t) {
                Log.e("AsyncTask", "OMGCrash", t);
                // maybe throw it again
                Toast.makeText(DownloadLoading.this,"There is a problem",Toast.LENGTH_SHORT).show();
                throw new RuntimeException(t);
            } finally {
                if (output != null) {
                    try {
                        output.flush();
                        output.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
                if (input != null) {
                    try {
                        input.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }
        }
        return null;
    }

    /**
     * Updating progress bar
     */
    protected void onProgressUpdate(Integer... progress) {
        // setting progress percentage
       pDialog.setProgress(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);

        if (error !=null){
            Toast.makeText(DownloadLoading.this, error.getMessage(),
                    Toast.LENGTH_SHORT).show();
        }else if(!running){
            Log.d("Faild","Download fail connection");

        }else{
            Toast.makeText(DownloadLoading.this, "Success", Toast.LENGTH_SHORT).show();
        }
    }
}

} }

Solution

I guess the Best solution to you is using Service with BroadCast

which Mean but all your download In Service

lets say

public class DowloadService extends Service {

 @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
     Bundle extras = intent.getExtras();
       your_data = extras.get() // just example
 for (int i = 0; i < passed.size(); i++) {

                        File file = getBaseContext().getFileStreamPath(passed.get(i).getActualFilename());
                          if (file.exists()){
                                countfile+=1;
                               pDialog.setMessage(" Exist / "+ConstantClass.filecount);
                          }else{
                        Log.d("checkFilecount" + i, "fileName: " + passed.get(i).getFileName());
                        String filename = passed.get(i).getFileName().substring(passed.get(i).getFileName().lastIndexOf("/") + 1);
                        Log.d("checkFile", "name: " + filename);
                        URL url = new URL(passed.get(i).getFileName());
                        System.out.println("Data::" + passed.get(i).getFileName());
                        URLConnection conection = url.openConnection();
                        conection.connect();
                        // getting file length
                        int lenghtOfFile = conection.getContentLength();
                        // input stream to read file - with 8k buffer
                        input = new BufferedInputStream(url.openStream(), 8192);
                        //input = new BufferedInputStream(url.openStream(), 20000);
                        System.out.println("Data::" + passed.get(i).getFileName());
                        System.out.println("Data::" + filename);
                        // Output stream to write file
                        output = new FileOutputStream(getApplicationContext().getFilesDir() + "/" + filename);

                        byte data[] = new byte[1024];

                        long total = 0;

                        while ((count = input.read(data)) != -1) {
                            total += count;
                            // publishing the progress....
                            // After this onProgressUpdate will be called
                            publishProgress((int) ((total * 100) / lenghtOfFile));

                            // writing data to file
                            output.write(data, 0, count);
                        }
                        countfile+=1;

               //  send broadcast with data you want
ntent.putExtra("dataType",dataType);
                intent.putExtra("getAccuracy",gpsSignal);
           LocalBroadcastManager.getInstance(getApplicationContext()).sendBroadcast(intent);

                            }
                        });
        return START_NOT_STICKY;
    }

}

and then in your activiy Setup Local BroadCast To get Data send

 private class BroadCastLocal extends BroadcastReceiver
    {

        @Override
        public void onReceive(Context context, Intent intent) {

            if (Constrains.PEDOMETERBROADCAST.equalsIgnoreCase(intent.getAction()))
            {
                int dataType = intent.getIntExtra("dataType",-1);


            }
        }

Now whenever the user start/end your activity .. the process will not be effected

Answered By - Elsunhoty