问题
In the Firebase Console once we import GCM project to FCM I saw that it creates a new API key. Will the old GCM API key also work?
回答1:
just create your project on FCM and follow below link
https://firebase.google.com/docs/cloud-messaging/android/client
and register your project and download google json file andput in your project
enjoy
来源：https://stackoverflow.com/questions/53951147/migrating-from-gcm-to-fcm