iosgame-centergkmatchmaker

Where is the auto-matched playerID stored before the connection is made?


I have implemented a custom matchmaker as a direct drop-in replacement to GKMatchmakerViewController, shown only when running in iOS6+. It is working perfectly, but there is one part of the UI in GKMatchmakerViewController that I can't seem to figure out.

When initiating a 2-player (request.minPlayers = 2, request.maxPlayers = 2) auto-match, GKMatchmakerViewController is able to update its UI with the display name and photo of the player that was found before they have changed to a connected state.

I use the following code to initiate an auto-match. A connection is made and the game starts and everything's fine.

[[GKMatchmaker sharedMatchmaker] findMatchForRequest:matchRequest withCompletionHandler:^(GKMatch *match, NSError *error) {
    if (error != nil) {
        // ...the error handling code...
    } else if (match != nil) {
        NSLog(@"An auto-match has been found: %@", match);

        if (match.expectedPlayerCount == 0) {
            [[GKMatchmaker sharedMatchmaker] finishMatchmakingForMatch:match];
        } else {
            NSLog(@"player IDs: %@", match.playerIDs);
        }
    }
}];

However, I'm not able to get the playerID until they have changed to GKPlayerStateConnected via:

- (void)match:(GKMatch *)match player:(NSString *)playerID didChangeState:(GKPlayerConnectionState)state;

When the match is found, that player is in GKPlayerStateUnknown. However, the match NSLog() in the code shows the playerID (it is definitely NOT the localPlayer's ID; the real number has been redacted):

An auto-match has been found: <GKMatch 0x210b2c90 expected count: 1 seqnum: 0
    G:1234567890:unknown
reinvitedPlayers:(
)>

The playerIDs array for the match (the second NSLog()) is empty as soon as the match is created, which makes sense because no connections have officially been made yet:

player IDs: (
)

I finally get to the questions (thank you for your patience):

1a) Where is the ID of the player in the unknown state coming from?

1b) It's in the match obviously but where exactly is it being stored? The only thing I see playerID-related is the array which is empty.

2) Is there some other (legal) way to obtain that playerID? i.e. before they change to a connected state


Solution

  • You had the playerID in your findMatchForRequest completion handler:

    [[GKMatchmaker sharedMatchmaker] findMatchForRequest:matchRequest withCompletionHandler:^(GKMatch *match, NSError *error) {
      // -- removed error checking code for short --
      puts( "PLAYER ID's:" ) ;
      for( NSString* ns in match )
          puts( [ ns UTF8String ] ) ; // FORMAT: G:37145177499. DO NOT FUDGE WITH THE STRING.
    
        [GKPlayer loadPlayersForIdentifiers:theMatch.playerIDs withCompletionHandler:^( NSArray *players, NSError *nsError ) {
          puts( "The REMOTE player aliases are:" ) ;
          if( !nsError )
            for( GKPlayer* p in players )
              puts( [p.alias UTF8String ] ) ;
       } ] ;
    }];
    

    You can then retrieve the player's alias etc from GKPlayer loadPlayersForIdentifiers:withCompletionHandler: