I am working on a simple turn-based word game, and I'm having a difficult time figuring out how invitations are working. When user A invites user B to a game, I want user B to be able to see this game in my custom match interface (ie a screen where all of user B's games are listed). Things are fine if user B clicks on the notification when he is invited to a game, but I still want the game to be visible through my own interface if user B just navigates to the app on his own.
Whenever this match interface screen appears, I am using [GKTurnBasedMatch loadMatchesWithCompletionHandler:] to get all of the local player's matches. With this, I would assume that user B would be able to see the match he has been invited to, but this new match doesn't show up. If I accept the invitation through the GKTurnBasedMatchmakerViewController, the user enters the game as expected, but what makes this even more puzzling is that if I open up my GKTurnBasedMatchmakerViewController and then cancel without accepting the invitation, a new match now shows up in my custom match interface, but it lacks the match data that was sent by user A.
To sum up, I am really just wondering how to properly display and accept GKTurnBasedMatch invitations with a custom interface (rather than having to use GKTurnBasedMatchmakerViewController). Thanks!
This question seems to be of interest to a couple people, so here's a rough approximation of what I ended up doing.
First of all, the reason new matches weren't showing up at all was just that I wasn't calling [GKTurnBasedMatch loadMatchesWithCompletionHandler:] every time I wanted the view to refresh like I though I was. So no real issue there as I recall.
The real issue was the case where I was receiving and displaying the new GKTurnBasedMatch, but none of the data (i.e. the opposing player's first move) was available. Essentially, [GKTurnBasedMatch loadMatchesWithCompletionHandler:] doesn't seem to guarantee providing you with the most up-to-date GKTurnBasedMatch objects available. To make sure the matches are up-to-date, I had to also call [match loadMatchDataWithCompletionHandler:], on each match returned by [GKTurnBasedMatch loadMatchesWithCompletionHandler:] (where match is one of those GKTurnBasedMatches). This returns the most current match data associated with that match as an NSData object. I was then able to use this NSData to make sure all the matches in my match table were refreshed to reflect the most recent changes in game center.
In short, use loadMatchDataWithCompletionHandler on your GKTurnBasedMatch objects to make sure their data is up to date.