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iosgame-centergamekit

How to invite players through game centre app in iOS 7?

I've already implemented auto-matchmaking, and tested it between two actual devices with different game centre accounts, so I know I've setup that part correctly: I can create a match, and send data between both the players. Now I'm implementing the invitations part.

The Game Center programming guide says:

The playersToInvite parameter is non-nil when your game is launched directly from the Game Center app to host a match. This parameter holds an array of player identifiers listing the players to invite into the match.

What I don't understand, is how to invite players through the game centre app. In the game centre app, I can see my game. When I click on it, in the top right corner there is a button with text: "..." . When I click on it, I see two options: "Play" and "Share". Clicking on "Play" launches my app.

Is there some code I need to implement for the Game center app to present me with the option of selecting friends to invite etc?

EDIT: It appears that the person in this post has almost the same problem as me: Definitive answer to what playersToInvite is for But no definitive answer so far, on how that data gets populated.

Solution

  • There are actually a couple of problems, both of which are on apples end:

    1. The documentation is not up to date. While it mentions to use [GKMatchMaker sharedMatchMaker].inviteHandler , it has actually been deprecated in iOS 7, but the documentation has not been updated to reflect this.

    2. It appears that there is no way you can invite players from the Game Center app. The documentation is incorrect in this case - the game centre UI does not provide any way for selecting the players. You invite players using the matchmaking view controller provided by game center.

    3. Instead of using GKMatchMaker.inviteHandler, one can implement GKLocalPlayerListener - but this hasn't been documented properly in the Game Center Programming guide. It is easy to implement as there are only two methods, and work in almost the same way as the deprecated handler.

    EDIT: There is a way to invite players from the game center app, but currently there is a bug in iOS 7, so that the game center app's flow in production, does not match the flow in the sandbox. As a result, one must navigate a much more cryptic flow to find the option to invite a player through the game center app. Currently only one player can be invited through the game center app, even if your app supports more than two players.