public function addAction($label, $url = 'index', $alerts = [], $order = null)
    {
        $this->actions[$url]         = new \stdClass();
        $this->actions[$url]->label  = $label;
        $this->actions[$url]->alerts = !is_array($alerts) ? [$alerts] : $alerts;

        if (is_null($order)) {
            $this->actions[$url]->order = count($this->actions);
        } else {
            $this->actions[$url]->order = $order;
        }

        return $this;
    }