public function responseAjax()
    {
        if (!$this->isAjax()) {
            $this->response->outputError403();
        }

        $action = $this->getPosted('action');

        if (empty($action)) {
            $this->outputJson(array('error' => $this->text('Unknown action')));
        }

        $this->outputJson(call_user_func(array($this, $action)));
    }