public void getItemListAsJSONObject() { // show ProgressBar mProgressBar.setVisibility(View.VISIBLE); String url = Data.URL_GET_SHOPS + "/" + mShop.getId(); RequestQueue requestQueue = Volley.newRequestQueue(getBaseContext()); JsonObjectRequest jsonObjectRequest = new JsonObjectRequest( Request.Method.GET, url, new JSONObject(), mResponseListener, mResponseErrorListener); jsonObjectRequest.setRetryPolicy(new DefaultRetryPolicy(4 * 1000, 3, 2)); requestQueue.add(jsonObjectRequest); }