public function get_sorted_plugins_list() {
        $names = core_component::get_plugin_list($this->subtype);

        $result = array();

        foreach ($names as $name => $path) {
            $idx = get_config($this->subtype . '_' . $name, 'sortorder');
            if (!$idx) {
                $idx = 0;
            }
            while (array_key_exists($idx, $result)) {
                $idx +=1;
            }
            $result[$idx] = $name;
        }
        ksort($result);

        return $result;
    }