在iOS上与Firebase断开连接

Question

I have a onDisconnectRemoveValue on a database reference to show when a user is currently 'in chat' and I would like to disconnect from the FIRDatabase when the user leaves the chat view controller - how can I trigger this disconnect function without quitting the app completely?

FIRDatabaseReference *connectedRef = [self.dbRef child:@".info/connected"];
    [connectedRef observeEventType:FIRDataEventTypeValue withBlock:^(FIRDataSnapshot * _Nonnull snapshot) {
        if (snapshot.value) {
            NSString *path = [NSString stringWithFormat:@"connections/%@/participants",self.refID];
            FIRDatabaseReference *participantsRef = [self.dbRef child:path];
            [participantsRef setValue:@{@"avatar":@"avatarURL",@"handle":[self senderDisplayName]} withCompletionBlock:^(NSError * _Nullable error, FIRDatabaseReference * _Nonnull ref) {
                [ref onDisconnectRemoveValue];
            }];
        }
    }];

Answer 1

You can call [[FIRDatabase database] goOffline]; to immediately trigger the connection to be closed. This will trigger the onDisconnect handler on the server, although there may be a delay before that runs.

Answer 2

You have to disconnect and reconnect the firebase connection with remove all observers between them.

Disconnect fire the onDisconnectRemoveValue after disconnect you have to reconnect to keep your firebase alive in order to continue work with other conversations but before reconnect you have to remove all observers to make sure that connectedRef don't fire again in reconnect and re add your values again.

[[FIRDatabase database] goOffline];

if (_connectedRef) {
    [_connectedRef removeAllObservers];
    _connectedRef = nil;
}

[[FIRDatabase database] goOnline];