/**
* Sub menu class
*
* @author Mostafa
*/
class Sub_menu {

/**
* Autoload method
* @return void
*/
public function __construct() {
add_action( ‘admin_menu’, array(&$this, ‘register_sub_menu’) );
}

/**
* Register submenu
* @return void
*/
public function register_sub_menu() {
add_submenu_page(
‘options-general.php’, ‘Submenu title’, ‘Submenu title’, ‘manage_options’, ‘submenu-page’, array(&$this, ‘submenu_page_callback’)
);
}

/**
* Render submenu
* @return void
*/
public function submenu_page_callback() {
echo ‘

‘;
}

}

new Sub_menu();