Android Volley - JsonArrayRequest with post parameters

Question

I'm using Volley to interact with an API. I need to send a post request with parameters to a service that returns a JSONArray.

I'm overriding the method protected Map<String, String> getParams() but it is not working:

JsonArrayRequest eventoReq = new JsonArrayRequest(Configuracion.URL_API_PROXIMOS_EVENTOS,
 new Response.Listener<JSONArray>() {
 @Override
 public void onResponse(JSONArray response) {
 Log.d(TAG, response.toString());
 hidePDialog();
 // Parsea json
 for (int i = 0; i < response.length(); i++) {
 try {
 JSONObject obj = response.getJSONObject(i);
 Evento evento = new Evento();
 evento.setCod_evento(obj.getInt("cod_evento"));
 evento.setTitulo(obj.getString("titulo"));
 evento.setDescripcion(obj.getString("descripcion"));
 evento.setDireccion(obj.getString("direccion"));
 evento.setImagen(obj.getString("imagen"));
 evento.setPuntuacion((float) obj.getDouble("puntuacion"));
 // Añade el evento al listado
 listaEventos.add(evento);
 } catch (JSONException e) {
 e.printStackTrace();
 }
 }
 // Actualiza el adaptador
 adapter.notifyDataSetChanged();
 }
 }, new Response.ErrorListener() {
 @Override
 public void onErrorResponse(VolleyError error) {
 VolleyLog.d(TAG, "Error: " + error.getMessage());
 hidePDialog();
 }
 }){
 @Override
 protected Map<String, String> getParams() {
 // Posting parameters to login url
 Map<String, String> params = new HashMap<String, String>();
 params.put("tag", "eventos_proximos_usuario");
 params.put("cod_usuario", cod_usuario);
 return params;
 }
 @Override
 public int getMethod() {
 return Method.POST;
 }
 };
 // Añade la peticion a la cola
 AppController.getInstance().addToRequestQueue(eventoReq);

• Qadir Hussain: what do you mean by not working?
• javier6_almansa: the API don't receive POST parameters

Answer 1

Try ... StringRequest instead..

Reference: https://android.googlesource.com/platform/frameworks/volley/+/master/src/main/java/com/android/volley/toolbox

JsonObjectRequest extends JsonRequest

whereas StringRequest extends Request

StringRequest eventoReq = new StringRequest(Request.Method.POST,Configuracion.URL_API_PROXIMOS_EVENTOS,
 new Response.Listener<String>() {
 @Override
 public void onResponse(String response) {
 Log.d(TAG, response.toString());
 hidePDialog();
try{
 JSONArray j= new JSONArray(response);
 // Parsea json
 for (int i = 0; i < j.length(); i++) {
 try {
 JSONObject obj = j.getJSONObject(i);
 Evento evento = new Evento();
 evento.setCod_evento(obj.getInt("cod_evento"));
 evento.setTitulo(obj.getString("titulo"));
 evento.setDescripcion(obj.getString("descripcion"));
 evento.setDireccion(obj.getString("direccion"));
 evento.setImagen(obj.getString("imagen"));
 evento.setPuntuacion((float) obj.getDouble("puntuacion"));
 // Añade el evento al listado
 listaEventos.add(evento);
 } catch (JSONException e) {
 e.printStackTrace();
 }
 }
// Actualiza el adaptador
 adapter.notifyDataSetChanged();
} catch (JSONException e) {
 e.printStackTrace();
 }
 }
 }, new Response.ErrorListener() {
 @Override
 public void onErrorResponse(VolleyError error) {
 VolleyLog.d(TAG, "Error: " + error.getMessage());
 hidePDialog();
 }
 }){
 @Override
 protected Map<String, String> getParams() {
 // Posting parameters to login url
 Map<String, String> params = new HashMap<String, String>();
 params.put("tag", "eventos_proximos_usuario");
 params.put("cod_usuario", cod_usuario);
 return params;
 }
 };
 // Añade la peticion a la cola
 AppController.getInstance().addToRequestQueue(eventoReq);

Me just a beginner hope it helps!!!

Answer 2

try like this, I think you don't need to override the getMethod() method.

Pass the method type (i.e Method.POST) name with in the JsonObjectRequest or JsonArrayRequest like below.

JsonObjectRequest jsonObjReq = new JsonObjectRequest(Method.POST,
 url, null,
 new Response.Listener<JSONObject>() {
 @Override
 public void onResponse(JSONObject response) {
 Log.d(TAG, response.toString());
 pDialog.hide();
 }
 }, new Response.ErrorListener() {
 @Override
 public void onErrorResponse(VolleyError error) {
 VolleyLog.d(TAG, "Error: " + error.getMessage());
 pDialog.hide();
 }
 }) {
 @Override
 protected Map<String, String> getParams() {
 // Posting parameters to login url
 Map<String, String> params = new HashMap<String, String>();
 params.put("tag", "eventos_proximos_usuario");
 params.put("cod_usuario", cod_usuario);
 return params;
 }
 };
// Adding request to request queue
AppController.getInstance().addToRequestQueue(jsonObjReq, tag_json_obj);

• iBobb: I'm trying to do the same so I implemented a custom Request but I still can't get it to work... This is my attempt: stackoverflow.com/questions/35971990/… As for your answer, it triggers the onErrorResponse...

Answer 3

I faced the same problem when I started to use Volley in my android project. I solved the problem by using StringRequest instead of JsonArrayRequest. for example if you want to show a ListView with some server data... Just use a simple StringRequest instead of JSONArrayRequest and implements the onResponse Methode like this :

public void onResponse(String response){
 try{
 JSONArray jsonArray=new JSONArray(response);
 for(int i=0;i<jsonArray.length();i++) {
 try {
 JSONObject jsonObject = jsonArray.getJSONObject(i);
 // do something
 } catch (JSONException e) {
 e.printStackTrace();
 } 
 }
 }catch (JSONException e2){
 e2.printStackTrace();
 }
 }
 }

Answer 4

StringRequest request = new StringRequest(Request.Method.POST, YourUrl, new Response.Listener<String>() {
 @Override
 public void onResponse(String response) {
 if (!response.equals(null)) {
 Log.e("Your Array Response", response); 
 } else {
 Log.e("Your Array Response", "Data Null");
 }
 }
 }, new Response.ErrorListener() {
 @Override
 public void onErrorResponse(VolleyError error) {
 Log.e("error is ", "" + error);
 }
 }) { 
 //This is for Headers If You Needed
 @Override
 public Map<String, String> getHeaders() throws AuthFailureError {
 Map<String, String> params = new HashMap<String, String>();
 params.put("Content-Type", "application/json; charset=UTF-8");
 params.put("token", ACCESS_TOKEN);
 return params;
 }
 //Pass Your Parameters here
 @Override
 protected Map<String, String> getParams() {
 Map<String, String> params = new HashMap<String, String>();
 params.put("User", UserName);
 params.put("Pass", PassWord);
 return params;
 }
 };
 RequestQueue queue = Volley.newRequestQueue(getApplicationContext());
 queue.add(request);