I was also having a problem with notifications that had to emit sound, when the app was in foreground everything worked correctly, however when the app was in the background the sound just didn't come out.
The notification was sent by the server through FCM, that is, the server mounted the JSON of the notification and sent it to FCM, which then sends the notification to the apps. Even if I put the sound tag, the sound does not come out in the backgound.
Even putting the sound tag it didn't work.
After so much searching I found the solution on a github forum. I then noticed that there were two problems in my case:
1 - It was missing to send the channel_id tag, important to work in API level 26+
2 - In the Android application, for this specific case where notifications were being sent directly from the server, I had to configure the channel id in advance, so in my main Activity I had to configure the channel so that Android knew what to do when notification arrived.
In JSON sent by the server:
{
"title": string,
"body": string,
"icon": string,
"color": string,
"sound": mysound,
"channel_id": videocall,
//More stuff here ...
}
In your main Activity:
@Background
void createChannel(){
Uri sound = Uri.parse("android.resource://" + getApplicationContext().getPackageName() + "/" + R.raw.app_note_call);
NotificationChannel mChannel;
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
mChannel = new NotificationChannel("videocall", "VIDEO CALL", NotificationManager.IMPORTANCE_HIGH);
mChannel.setLightColor(Color.GRAY);
mChannel.enableLights(true);
mChannel.setDescription("VIDEO CALL");
AudioAttributes audioAttributes = new AudioAttributes.Builder()
.setContentType(AudioAttributes.CONTENT_TYPE_SONIFICATION)
.setUsage(AudioAttributes.USAGE_ALARM)
.build();
mChannel.setSound(sound, audioAttributes);
NotificationManager notificationManager =
(NotificationManager) getApplicationContext().getSystemService(Context.NOTIFICATION_SERVICE);
notificationManager.createNotificationChannel(mChannel);
}
}
This finally solved my problem, I hope it helps someone not to waste 2 days like I did. I don't know if it is necessary for everything I put in the code, but this is the way. I also didn't find the github forum link to credit the answer anymore, because what I did was the same one that was posted there.