How to get String response from JSONObject in Volley

Question

I have created JSONRequest by using volley, It successfully hits the service, I checked the service end, It receives the data, and send "Success" in return.

The problem is that, Service returns String in output, and Volley excepts some JSON Data in output. So it executes the onError Method, instead of onResponse.

Kindly guide me how to make it accept string response, or is it not possible when you are using JSONObjectas request.

    Request<JSONObject> jsonObjectRequest = new JsonObjectRequest(Request.Method.POST, "http://192.168.0.101:8888/api/services/mytest",
            jsonParent, new Response.Listener<JSONObject>() {
        @Override
        public void onResponse(JSONObject response) {
            Log.d("Success", response.toString());
            deleteFile();
        }
    }, new Response.ErrorListener() {
        @Override
        public void onErrorResponse(VolleyError error) {
            Log.d("Error", error.toString());
            deleteFile();
        }

    RequestQueue requestQueue = Volley.newRequestQueue(getApplicationContext());
    requestQueue.add(jsonObjectRequest);

Answer 1

You can use StringRequest instead JSONRequest.

StringRequest stringRequest = new StringRequest(methodType, url,
                    new Response.Listener<String>() {
                        @Override
                        public void onResponse(String response) {

                        }
                    }, new Response.ErrorListener() {
                @Override
                public void onErrorResponse(VolleyError error) {

                }
            }){
                @Override
                public Map<String, String> getHeaders() throws AuthFailureError {
                    return headers == null ? super.getHeaders() : headers;
                }

                @Override
                public byte[] getBody() throws AuthFailureError {
                    return "Your JSON body".toString().getBytes();
                }
            };

getheaders method is to add custom headers if you want and getBody to supply request body.

Answer 2

For those who still need to send raw Json and receive a String as response:

By default, the body consists of the request parameters in application/x-www-form-urlencoded; charset=UTF-8 format for StringRequest. When overriding getBody(), as Nayan suggested correctly, consider overriding getBodyContentType() as well to match the new body format. For Json it should be application/json.

String url = "www.google.com";

HashMap<String, Object> params = new HashMap<>();
params.put("key1", "Android");
params.put("isCool", true);

StringRequest request = new StringRequest(Request.Method.POST, url, 
        new Response.Listener<String>() {
            public void onResponse(String response) {

            }
        },
        new Response.ErrorListener() {
            public void onErrorResponse(VolleyError error) {

            }
        }
    ) {
        public byte[] getBody() {
            return new JSONObject(params).toString().getBytes();
        }
        public String getBodyContentType() {
            return "application/json";
        }
    };

Volley.newRequestQueue(this).add(request);