Estou fazendo upload de string e photo.and está funcionando bem. Agora, quero mostrar a barra de progresso durante o upload de dados com porcentagem, mas a porcentagem mostra muito rapidamente a 100 porcentagem e leva mais tempo para fazer o upload e, finalmente, chegar ao método de pós-execução.

protected class upload_images extends AsyncTask<String, Integer, String> {
        ProgressDialog progressDialog;
            @Override
            protected void onPreExecute() {
                super.onPreExecute();
               // showDialog(progress_bar_type);
                progressDialog = new ProgressDialog(Accept_Report.this);
                progressDialog.setCancelable(false);
                //  dialog.setCanceledOnTouchOutside(false);
                progressDialog.setIndeterminate(false);
              //  progressDialog.setMax(100);
                progressDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
               // progressDialog.setProgress(0);
                progressDialog.setMax(100);
               // progressDialog.setMessage("Loading ...");
                progressDialog.show();
             //  ProgressBar progressBar = (ProgressBar)findViewById(R.id.progressBar2);
            }
            @Override
            protected String doInBackground(String... params) {
                URL url;
                HttpURLConnection connection = null;
                String http=Util.URL+"reports/media/create";
                try {
                    url = new URL(http);
                    connection = (HttpURLConnection) url.openConnection();
                    connection.setDoInput(true);
                    connection.setRequestMethod("POST");
                  /*  connection.setConnectTimeout(50000);
                    connection.setReadTimeout(50000);*/
                    connection.setRequestProperty("Content-Type", "application/json");
                    connection.setRequestProperty("Content-Language", "en-US");
                    String encoded = Base64.encodeToString(("app" + ":" + "sFif4au7wet8gpsT0boK1oM2Yud6M1").getBytes("UTF-8"), Base64.NO_WRAP);
                    connection.setRequestProperty("Authorization", "Basic " + encoded);
                    connection.setUseCaches(false);
                    connection.setDoOutput(true);
                    connection.connect();

                    jsonArray = new JSONArray();

                    right = send_right.toString().replaceAll("\\[", "").replaceAll("\\]", "");
                    if((right!=null)&&(right!="")) {
                        JSONObject pnObj = new JSONObject();
                        pnObj.put("comments", right_cm);
                        pnObj.put("section", right_sec);
                        pnObj.put("pictures", right);
                        jsonArray.put(pnObj);
                    }    

                       // return totalSize;

                     JSONObject jsonParam = new JSONObject();
                     jsonParam.put("media", jsonArray);

                    //Send request


                        int count = 0;
                        OutputStream wr = connection.getOutputStream();
                        InputStream inputStream = null;
                        byte[] payload = jsonParam.toString().getBytes("UTF-8");
                        int totalSze = payload.length;
                        Log.e("Total size ", "" + totalSze);
                        int bytesTransferred = 0;
                       int chunkSize = (2*totalSze)/100;
                        boolean last_loop = false;
                       // publishProgress(0);

                        while (bytesTransferred < totalSze) {

                            Log.e("bytes transferred", "" + bytesTransferred);
                            int nextChunkSize = totalSze - bytesTransferred;
                            Log.e("nextchunck",""+nextChunkSize);

                            //int writer_size = wr.toString().getBytes("UTF-8").length;
                            Log.e("chunk size", "" + chunkSize);
                            if (nextChunkSize > chunkSize) {
                                nextChunkSize = chunkSize;
                            }


                            wr.write(payload, bytesTransferred, nextChunkSize);
                            bytesTransferred += nextChunkSize;
                            Log.e("byte",""+wr.toString().getBytes("UTF-8").length);

                            Log.e("progress-transferred", "" + bytesTransferred +" total "+totalSze);


                            double cal = (( (double)bytesTransferred / (double) totalSze) * 100);

                            double rounded = (double) Math.round(cal * 100.0) / 100.0;

                            Log.e("progress",""+(int)rounded);

                            publishProgress((int)rounded);

                        wr.flush();
                        wr.close();

                            }catch(Exception e){
                                Log.d("Exception", e.toString());
                            }
                        }*/
                        Log.e("While loop exit", "");
                      /*  wr.flush ();
                        wr.close();*/


                    }catch (OutOfMemoryError e)
                    {
                        e.printStackTrace();
                    }

                    //Get Response
                    StringBuilder sb = new StringBuilder();
                    HttpResultimage =connection.getResponseCode();
                    Log.e("res",""+HttpResultimage);

                    if(HttpResultimage==204)
                    {
                        BufferedReader br = new BufferedReader(new InputStreamReader(connection.getInputStream(),"utf-8"));
                        String line = null;
                        while ((line = br.readLine()) != null) {
                            sb.append(line + "\n");
                        }
                        br.close();
                        System.out.println("" + sb.toString());
                    }else{
                    }



                } catch (Exception e) {
                    e.printStackTrace();
                    return null;
                } finally {
                    if(connection != null) {
                        connection.disconnect();
                    }
                }
                return null;
            }
            @Override
            protected void onProgressUpdate(Integer... values){
                super.onProgressUpdate(values);
              //  Log.e("dfsf",""+values[0]);
                progressDialog.setProgress(values[0]);
             //   progressDialog.setProgress(values[0]);

            }

            @Override
            protected void onPostExecute(String result) {
                if (HttpResultimage==204) {
                  progressDialog.dismiss();
                }
            }
        }