Opencart 3.0 -如何通过事件系统从目录控制器添加内联javascript代码？

class Event {
    private $registry;
    private $data = array();

    public function __construct($registry) {
        $this->registry = $registry;
    }

    public function trigger($event, &$args = array()) {
        foreach ($this->data as $key => $value) {
            $action = new Action($value['action']);

            $result = $action->execute($this->registry, $args);

            if ($result && $action->output) {
                return $result;
            }
        }
    }

    public function register($event, $action, $priority = 0) {
        $this->data[$priority][$event] = array(
            'action' => $action
        );
    }

    public function unregister($event) {
        foreach ($this->data as $priority => $events) {
            if (isset($events[$event])) {
                unset($this->data[$priority][$event]);
            }

            if (!$this->data[$priority]) {
                unset($this->data[$priority]);
            }
        }
    }
}

class Event {
    // ...

    public function addInlineJavascript($javascript) {
        $this->data['inline_javascript'] = array(
            'action' => function($registry, &$args) use ($javascript) {
                $registry->get('response')->addOutput('<script>' . $javascript . '</script>');
            }
        );
    }
}

public function index() {
    // ...
}

$this->event->addInlineJavascript('alert("Hello, Opencart!");');