public static function extendListColumns($callback)
    {
        $calledClass = self::getCalledExtensionClass();
        Event::listen('backend.list.extendColumns', function ($widget) use ($calledClass, $callback) {
            if (!is_a($widget->getController(), $calledClass)) {
                return;
            }
            call_user_func_array($callback, [$widget, $widget->model]);
        });
    }