StringRequest request = new StringRequest(Request.Method.POST, "http://demo.alumagubi.com/dsucasa/api/user/login",
                new Response.Listener<String>() {
                    @Override
                    public void onResponse(String response) {
                        Log.e("RESPONSE", response);
                        volleyCallback.onResponse(response);
                    }
                },
                new Response.ErrorListener() {
                    @Override
                    public void onErrorResponse(VolleyError error) {
                        volleyCallback.ErrorListener(error.getMessage());
                        error.printStackTrace();
                    }
                })
        {
            @Override
            public Map<String, String> getHeaders() throws AuthFailureError {
                Map<String, String> header = new HashMap<>();
                header.put("x-api-key","883F72561AFD4FAEB3A20E814DE4881E");
                header.put("Accept-Charset","utf-8");
                header.put("Accept","application/json");
                return header;
            }

            @Override
            protected Map<String, String> getParams() throws AuthFailureError {
                Map<String,String> params = new HashMap<>();
                params.put("phone","123");
                params.put("password","123");

                return params;
            }

        };

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