[10.4.1 内容观察者的注册过程](10.4.1%E5%86%85%E5%AE%B9%E8%A7%82%E5%AF%9F%E8%80%85%E7%9A%84%E6%B3%A8%E5%86%8C%E8%BF%87%E7%A8%8B.md) [10.4.2 数据更新的通知过程](10.4.2%E6%95%B0%E6%8D%AE%E6%9B%B4%E6%96%B0%E7%9A%84%E9%80%9A%E7%9F%A5%E8%BF%87%E7%A8%8B.md)