php - I can't load any controller but the one with the module name in CodeIgniter HMVC -

so, i'm developing website in codeigniter 3 hmvc, , i've got following folder structture inside application folder:

core     my_controller.php modules     login         controllers             keep_logged.php             login.php 

so, my_controller (i'm using parent controllers):

<?php (defined('basepath')) or exit('no direct script access allowed');  class my_controller extends mx_controller   {      function __construct()  {         parent::__construct();          $this->load->module("template");                 $this->load->module("login/keep_logged");          $this->keep_logged->cookie_authenticate();          $exceptions = array("login", "login/authenticate");          if ($this->session->user_id == null && !in_array(uri_string(), $exceptions))    {             redirect("/login", "refresh");         }     }  } 

and keep_logged.php

<?php   class keep_logged extends my_controller  {     function __construct()  {         parent::__construct();          $this->load->model("login/login_model");         $this->load->helper("cookie");     }      function cookie_authenticate()  {         if ($user = $this->login_model->check_login(get_cookie("user_email"), get_cookie("user_password"), true))   {             $this->session->set_userdata(array(                 "user_id" => $user->user_id,                 "user_email" => $user->email,                 "user_name" => $user->name,                 "user_kind" => $user->kind             ));         }     } } 

my problem can't load keep_logged.php controller, though can load login.php (or controller same name it's module). how can fix ? errors every time.

a php error encountered

severity: notice

message: undefined property: ci::$keep_logged

filename: mx/controller.php

line number: 59

-

an uncaught exception encountered

type: error

message: call member function cookie_authenticate() on null

filename: d:\xampp\htdocs\cihmvc\application\core\my_controller.php

line number: 13

you try call method of child class in parent class. move cookie_authenticate() method my_controller , call in $this->cookie_authenticate(). don`t forget move staff keep_logged constructor my_controller constructor.