unsubscribe method
Remove from the center the subscribers of notificationId
.
Implementation
Future<void> unsubscribe(String notificationId) async {
if (_notifications.containsKey(notificationId)) {
final subscribers = _notifications[notificationId]!.toList();
for (final subscriber in subscribers) {
await subscriber.cancel();
}
if (_notifications[notificationId]?.isEmpty ?? false) {
_notifications.remove(notificationId);
}
}
}