title: Volley sends null parameters to server
body: <p>I'm trying to send JSON parameter but server is receiving them as nulls values,
  i tried to request it from Postman and it works perfect, i don't know what the problem is with volley  i followed the instructions <a href="https://stackoverflow.com/questions/19837820/volley-jsonobjectrequest-post-request-not-working">here</a> but it didn't make sense</p>
  
  <p>here is my code     </p>
  
  <pre><code>String url = "http://10.10.10.166:8080/SystemManagement/api/Profile/Login";
      JSONObject jsonObject=new JSONObject();
  
      try {
          jsonObject.put("user_id","Test user name");
          jsonObject.put("user_password","test password");
      } catch (JSONException e) {
          e.printStackTrace();
      }
      System.out.println(jsonObject.toString());
  
      JsonObjectRequest jsonObjectRequest = new JsonObjectRequest(  Request.Method.POST, url, jsonObject,
              new Response.Listener&lt;JSONObject&gt;() {
  
  
  
                  @Override
                  public void onResponse(JSONObject response) {
                      Toast.makeText(Login.this, response.toString(),Toast.LENGTH_SHORT).show();
                  }
              },
              new Response.ErrorListener() {
                  @Override
                  public void onErrorResponse(VolleyError error) {
                      System.out.println(error.toString());
  
                  }
              });
      //add request to queue
      queue.add(jsonObjectRequest);
  </code></pre>