Question

Can’t see why this is happening, but when I use Bluetooth to send data to connected peers, they receive the data perfectly well but then immediately disconnect making further interaction impossible. Can anyone give any indication as to why this might be happening? I tried changing the timeout to 60 seconds, I tried reducing the amount of data sent to less than 500 bytes, and still I get this strange situation where peers will immediately disconnect from one another. Is it maybe because I’m using a GKSession to initialise the network, then a GKPeerPicker for people to connect to it?

Here’s my data sending-and-receiving code. This is mostly temporary and will probably change to accommodate large amounts of data, but right now I just want to establish a stable connection.

-(void)transmitWholeClusterToPeer:(NSString *)peerID{
NSMutableData *data = [NSMutableData data];
NSKeyedArchiver *encoder = [[NSKeyedArchiver alloc]initForWritingWithMutableData:data];

[encoder encodeInt:0 forKey:@"Mode"];
[encoder encodeObject:clusterMap.header forKey:@"Header"];
[encoder finishEncoding];

NSArray *peerList = [[[NSArray alloc] initWithObjects:peerID, nil] copy];

[network sendData:data toPeers:peerList withDataMode:GKSendDataReliable error:nil];
[encoder autorelease];      
[peerList autorelease];

}

-(void)receiveData:(NSData *)data fromPeer:(NSString *)peer inSession:(GKSession *)session
       context:(void *)context{
NSKeyedUnarchiver *decoder = [[NSKeyedUnarchiver alloc] initForReadingWithData:data];
int mode = [decoder decodeIntForKey:@"Mode"];

switch (mode) {
    case 0:
        clusterMap.header = [decoder decodeObjectForKey:@"Header"];
        break;
    default:
        break;
}

}

Answer 1

I can’t say for sure this is the definitive answer, but I have solved the problem after a fashion by removing GKPeerPicker and implementing my own Client-Server setup code that generates ‘keep alive’ pings itself. I think the problem really was only that I was setting up a session manually, then using the Peer Picker to connect to it. It seems that Peer Pickers are only stable and useful when they are connecting to other Peer Pickers.