public function set_submission_viewed($submission) {
        $params = array(
            'objectid' => $submission->id,
            'context' => $this->context,
            'courseid' => $this->course->id,
            'relateduserid' => $submission->authorid,
            'other' => array(
                'workshopid' => $this->id
            )
        );

        $event = \mod_workshop\event\submission_viewed::create($params);
        $event->trigger();
    }