2018 年 4 月 10 日,Google 弃用了 GCM。GCM 服务器和客户端 API 已于 2019 年 5 月 29 日被移除,目前对这些 API 的任何调用预计都将失败。
Google Cloud Messaging, deprecated April 10 2018, has been deactivated and removed from Google's APIs. For equivalent functionality, use Firebase Cloud Messaging (FCM), which inherits the reliable and scalable GCM infrastructure, plus many new features.