Error in Json in volley to Android Studio

Question

I want to call a Api But Reception error is running !! I have a Json api A Java class to call Please help me fix the error!

my jeson:

my class in load data:

 public void loadproductview() {
        String url = "https://alphaonline.ir/index.php?route=api32/product/product&token=3344556677";

        Response.Listener<JSONObject> objectListener = new Response.Listener<JSONObject>() {
            @Override
            public void onResponse(JSONObject response) {
                try {
                    String name = response.getString("name");

                    txt_name.setText(name);

                } catch (JSONException e) {
                    e.printStackTrace();
                }
            }
        };
        Response.ErrorListener errorListener = new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError error) {
                Toast.makeText(ProductActivity.this, error.toString(), Toast.LENGTH_SHORT).show();
            }
        };

        Map<String, String> params = new HashMap();
        params.put("product_id", "237");
        JSONObject parameters = new JSONObject(params);

        JsonObjectRequest request = new JsonObjectRequest(Request.Method.POST, url, parameters, objectListener, errorListener);
        MySingleton.getInstance(getApplicationContext()).addToRequestQueue(request);
    }

Answer 1

You are initializing JSONObject with Map which is wrong> Directly put the values in JSONObject.

   JSONObject parameters = new JSONObject();
    parameters.put("product_id", "237");

Try this:-

public void loadproductview() {
    String url = "https://alphaonline.ir/index.php?route=api32/product/product&token=3344556677";

    Response.Listener<JSONObject> objectListener = new Response.Listener<JSONObject>() {
        @Override
        public void onResponse(JSONObject response) {
            try {
                String name = response.getString("name");

                txt_name.setText(name);

            } catch (JSONException e) {
                e.printStackTrace();
            }
        }
    };
    Response.ErrorListener errorListener = new Response.ErrorListener() {
        @Override
        public void onErrorResponse(VolleyError error) {
            Toast.makeText(ProductActivity.this, error.toString(), 
            Toast.LENGTH_SHORT).show();
        }
    };

    JSONObject parameters = new JSONObject(params);
    parameters.put("product_id", "237");
    JsonObjectRequest request = new JsonObjectRequest(Request.Method.POST, URL, 
    parameters, objectListener, errorListener);
    MySingleton.getInstance(getApplicationContext()).addToRequestQueue(request);
    }

Answer 2

I am not sure how you handle the singleton instance of the request, so instead of this:

MySingleton.getInstance(getApplicationContext()).addToRequestQueue(request);

do this:

RequestQueue queue = Volley.newRequestQueue(this);
queue.addToRequestQueue(request);