public function get_user_list() {
        global $CFG, $SITE;

        $courseid = $SITE->id;
        if (!empty($this->course)) {
            $courseid = $this->course->id;
        }
        $context = context_course::instance($courseid);
        $limitfrom = empty($this->showusers) ? 0 : '';
        $limitnum  = empty($this->showusers) ? COURSE_MAX_USERS_PER_DROPDOWN + 1 : '';
        $courseusers = get_enrolled_users($context, '', $this->groupid, 'u.id, ' . get_all_user_name_fields(true, 'u'),
                null, $limitfrom, $limitnum);

        if (count($courseusers) < COURSE_MAX_USERS_PER_DROPDOWN && !$this->showusers) {
            $this->showusers = 1;
        }

        $users = array();
        if ($this->showusers) {
            if ($courseusers) {
                foreach ($courseusers as $courseuser) {
                     $users[$courseuser->id] = fullname($courseuser, has_capability('moodle/site:viewfullnames', $context));
                }
            }
            $users[$CFG->siteguest] = get_string('guestuser');
        }
        return $users;
    }