I am trying out Firebase Notifications. I was able to get the Notification to work properly using this documentation. The message was received and I was able to send a notifica
Notifications will be delivered to your app's onMessageReceived
only when the app is in the foreground. When your app is backgrounded or not running, the system will handle the notification and display it in the system tray.
The Firebase documentation explains it as:
Notification message - FCM automatically displays the message to end-user devices on behalf of the client app. Notification messages have a predefined set of user-visible keys.
Data message - Client app is responsible for processing data messages. Data messages have only custom key-value pairs.
Since you want your code to always be invoked, you'll need to send data messages. You cannot send data messages from the Firebase Console. But if you already send messages from an app server, the process for sending data messages and notification messages is the same there. The only difference is in the JSON structure, where a data messages doesn't have a notification
object. From the documentation on data messages
{
"to" : "bk3RNwTe3H0:CI2k_HHwgIpoDKCIZvvDMExUdFQ3P1...",
"data" : {
"Nick" : "Mario",
"body" : "great match!",
"Room" : "PortugalVSDenmark"
},
}