FCM when app in background

Hi,

The FCM works fine when the app is in foreground and a push comes, but when the app is in background and the system tray notification is clicked , it just opens up the app without passing any intent extras. I have added the click_action in Notification Payload from Advanced option of Firebase Console to open an activity but it dosen’t work. I have also added the intent-filter ( handle backgound app section) as in documentation.

How can i open a specific activity using FCM service along with the data i pass when the app is in background or exit state.

[wassupnari]

Hi @kroikie

I have a follow up question. According to this documentation, the notification will be delivered to the device’s system tray when the app is in background which means onMessageReceived() won’t get called, but I wonder if there’s any way that I can customize the icon in the notification view. Currently, it shows default white icon.

[pratikbutani]

After a deep search, I have found what is going on: There are two types of messages in FCM:

• display-messages: These messages only work when your app is in foreground
• data-messages: Theses messages work even if your app is in background

Firebase team have not developed a UI to send data-messages to your devices.

To achieve this, you have to do a POST to the following URL:

https://fcm.googleapis.com/fcm/send

And the following headers:

• Key: Content-Type, Value: application/json
• Key: Authorization, Value: key=<your-server-key>

Body:

{
    "data": {
        "my_custom_key" : "my_custom_value",
        "other_key" : true
     },
    "registration_ids": ["your-device-token","your-device2-token","your-device3-token"]
}

To get your server key, you can find it in the firebase console: Your project -> settings -> Project settings -> Cloud messaging -> Server Key

Hope this helps!

Ref: How to handle notification when app in background in firebase