/**
  * Run asyn task.
  *
  * @param params the params
  */
 private void runAsynTask(String params[]) {
   mTask = new DownloadFileFromURL();
   if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
     mTask.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR, params);
   } else {
     mTask.execute(params);
   }
 }
 @Override
 public void onBackPressed() {
   if (mTask != null) {
     mTask.cancel(false);
   }
   super.onBackPressed();
 }