问什么在_topic_replied.blade.php 获取不到 toDatabase () 返回的数据，该页面显示是空白页面

public function toDatabase($notifiable)
{
$topic = $this->reply->topic;
$link = $topic->link(['#reply' . $this->reply->id]);

    // 存入数据库里的数据
    return [
        'reply_id' => $this->reply->id,
        'reply_content' => $this->reply->content,
        'user_id' => $this->reply->user->id,
        'user_name' => $this->reply->user->name,
        'user_avatar' => $this->reply->user->avatar,
        'topic_link' => $link,
        'topic_id' => $topic->id,
        'topic_title' => $topic->title,
    ];
}