Xamarin Forms Android not receiving Push notifications when closed

Question

I am following this walkthrough for creating push notifications into a Xamarin forms app

https://docs.microsoft.com/en-us/azure/notification-hubs/notification-hubs-andro

Answer 1

try to put JSON key 'notification' in your request to firebase API but instead use 'data'

{
 "to": "/topics/journal",
 "notification": {
 "title" : "title",
 "text": "data!",
 "icon": "ic_notification"
  }
}

in this case,these messages trigger the onMessageReceived() callback only when your app is in foreground

{
 "to": "/topics/dev_journal",
 "data": {
   "text":"text",
   "title":"",
   "line1":"Journal",
   "line2":"刊物"
  }
}   

in this case,theses messages trigger the onMessageReceived() callback even if your app is in foreground/background/killed

but this is a topic that depends also on the device and that FCM has no total control over.

the more you could refer to https://stackoverflow.com/a/37845174/10768653

and https://stackoverflow.com/a/43131488/10768653