将表单数据发布到服务器（Android）

我需要将我的注册表格详细信息提交给服务器api。我通过在按钮click上调用一个函数尝试了一种方法，但是服务器上没有任何内容。我需要将数据发布为Content-type：Form-Data，因为服务器对其他任何内容均无响应。请帮助我，谢谢！

 public class Login extends AsyncTask<String, Void, Void> {

        String userName;
        String password;

        public Login(String user, String pass) {
           userName = user;
            password = pass;
        }

        protected void onPreExecute() {
            super.onPreExecute();

        }



        protected Void doInBackground(String... params) {
            OkHttpClient client = new OkHttpClient();
                RequestBody formBody = new FormBody.Builder()
                        
                        .addEncoded("user",userName)
                        .addEncoded("pass",password)
                        .build();

            Request request = new Request.Builder()
                    .url("http://www.autotrack.rs/android_juzna_backa/login.php")
                    .post(formBody)
                    .build();

            try {
                Call call = client.newCall(request);
                Response response = call.execute();
                System.out.println(response.body().string());

            }catch (Exception m)
            {
                m.printStackTrace();
            }
            Response response = null;
            try {
                response = client.newCall(request).execute();
                System.out.println(response.body().string());

            } catch (IOException e) {
                e.printStackTrace();
            }
            if(!response.isSuccessful())
            {
                try {
                    throw new IOException("Unexpected: "+response);
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            return null;
            }