使用JsonObjectRequest的POST数据不起作用

Question

我正在尝试使用JSONObjectRequest发布数据，但是它不起作用。它发布空值。我怎么解决这个问题 ？这是我的代码。

        public void getData(){
    String url = "http://address.com";

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

    JsonObjectRequest jsonObjectRequest = new JsonObjectRequest(Request.Method.POST, url, parameters, new Response.Listener<JSONObject>() {
        @Override
        public void onResponse(JSONObject response) {
            try {
                String name_server = response.getString("name");
                String number_server = response.getString("number");
                textView.setText(name_server);
                number.setText(number_server);

            } catch (JSONException e) {
                e.printStackTrace();
            }

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

        }
    });

    MySingleton.getInstance(getApplicationContext()).addToRequestque(jsonObjectRequest);
}

这是我的PHP代码

<?php

   $name = $_POST["name"];
   $number = $_POST["number"];

   echo json_encode(array("name"=>"$name","number"=>"$number"));

  ?>

但请不要帮助我。