I am using GameKit on a basic level right now. I am able to connect two devices and send messages between them.
I have 3 devices, we'll call them device A, B and C.
I am able to connect A to B, A to C, and B to C, as individual setups.
If I connect A to B, then attempt to connect B to C, Device C will show that Device B is available, but device B continues to spin and say "Looking for available iPod, iPhones..."
In peerPickerController:sessionForConnectionType:
, when I am attempting to connect B to C, I am trying to have device B reuse its same GKSession
that it is using in its connection to A... because if I create a new session on device B, it is able to connect to Device C but drops the connection to device A.
Here is the sessionForConnectionType
:
-(GKSession*)peerPickerController:(GKPeerPickerController *)picker sessionForConnectionType:(GKPeerPickerConnectionType)type {
// session is a synthesized GKSession
if (session == nil) {
session = [[GKSession alloc] initWithSessionID:nil displayName:@"" sessionMode:GKSessionModePeer];
session.delegate = self;
}
return session;
}
I ended up going with a Server / Client setup, which is easier to manage. This way, there is only one Server PeerID, as opposed to a Server PeerID for every connection. I wasn't able to find many good examples, so I've included the basic GameKit Server / Client code here.
// if the device in an ipad, treat it as a host / server
if ([[[UIDevice currentDevice] model] isEqualToString:@"iPad"]) {
isHost = YES;
} else {
isHost = NO;
}
// monitor if this device is connected to another device
isConnected = NO;
}
#pragma mark GameKit Methods
// Called when a change in the connection state is detected
- (void)session:(GKSession *)session peer:(NSString *)peerID didChangeState:(GKPeerConnectionState)state {
NSLog(@"Session:Peer:%@ Did Change State", peerID);
Globals *globals = [Globals shareData];
switch (state) {
case GKPeerStateConnected:
NSLog(@"GKPeerStateConnected");
[globals.localSession setDataReceiveHandler:self withContext:nil];
// if this device is not the host and is not connected yet...
if (!isHost && !isConnected) {
// update variables, save the Server PeerId and the local Session so we can use them later
isConnected = YES;
serverSession = peerID];
localSession = session;
}
break;
case GKPeerStateDisconnected:
NSLog(@"GKPeerStateDisconnected");
break;
case GKPeerStateAvailable:
NSLog(@"GKPeerStateAvailable");
if (!isHost) {
NSLog(@"Attempting to Connect...");
// the server is available, try to connect to it
[session connectToPeer:peerID withTimeout:20];
}
break;
case GKPeerStateConnecting:
NSLog(@"GKPeerStateConnecting");
break;
case GKPeerStateUnavailable:
NSLog(@"GKPeerStateUnavailable");
break;
}
}
// Called if this device receives a request for a connection
// This should only happen on the Server device
-(void)session:(GKSession *)session didReceiveConnectionRequestFromPeer:(NSString *)peerID {
NSLog(@"Received Connection Request From %@", peerID);
// Accept the connection request from the peer
[session acceptConnectionFromPeer:peerID error:nil];
}
- (void)receiveData:(NSData *)data fromPeer:(NSString *)peer inSession:(GKSession *)session context:(void *)context {
NSLog(@"Received Data");
}
-(void)session:(GKSession *)session didFailWithError:(NSError *)error {
NSLog(@"Session Failed: %@", error);
}
// Connected to a UIButton
-(IBAction)sendData {
NSLog(@"Sending Data ...");
}
// Connected to a UIButton
-(IBAction)beginConnection {
Globals *globals = [Globals shareData];
// Set this up as a server
if (isHost) {
GKSession *session = [[GKSession alloc] initWithSessionID:@"" displayName:@"Server" sessionMode:GKSessionModeServer];
session.delegate = self;
session.available = YES;
NSLog(@"Setting Server Session Peer:%@", session.peerID);
globals.localSession = session;
}
// or set it up as a client
else {
GKSession *session = [[GKSession alloc] initWithSessionID:@"" displayName:nil sessionMode:GKSessionModeClient];
session.delegate = self;
session.available = YES;
NSLog(@"Setting CLIENT Session Peer:%@", session.peerID);
globals.localSession = session;
}
}
... Dealloc, etc...
@end