GameCenter login alert

Question

In a game I am developing using GameCenter, I want to handle the following scenario:

1. the user starts up the game. He is shown the system alert that prompts him to

Answer 1

May be the link will helpful (First three paragraphs): http://developer.apple.com/library/ios/#documentation/NetworkingInternet/Conceptual/GameKit_Guide/Users/Users.html#//apple_ref/doc/uid/TP40008304-CH8-SW9

The main point is in a rectangle "Important".

Answer 2

The behavior is something to the effect of, after N unsuccessful attempts - disable GameCenter for the app. Restarting the app or going to login in gamecenter itself will get it back online.

I forget which doc I read this in, but there is an Apple doc out there that explains this behavior.

Answer 3

I'm facing the same issue. Though I couldn't find a way to enforce poping up the same dialog for logging into Game Center, I did find a way to implement a warning message saying 'gamecenter is disabled' when user clicks on a leaderboard icon:

if([GKLocalPlayer localPlayer].authenticated == NO)
{
// Prompt a warning message alert saying game center is disabled
}
else
{
// Proceed with opening leaderboard
}

Hope this helps!

Answer 4

It appear that iOS will disable Game Center completely and prevent it from prompting after the user chooses to Disable Game Center (the option would appear on your fifth 5th Game Center cancel sign in).

To restore the device to the original state where the login prompt will appear again. Simply sign in using the Game Center app using a normal working Game Center account (non Tester). Once you are in, Sign Out. It should start prompting you again on within your app.

Answer 5

I am playing around with Game Center myself right now I have seen the very same behavior. There is nothing in the documentation saying anything about the dialog only showing up the first couple of times. In my case I would like a way to tell beforehand if the user is already logged into Game Center, so that I can behave appropriately. But now I can not know this before the dialog is shown to the user.

Since we are running in the sandbox during development this behavior might of course be something that behaves differently during production but this is not an easy thing to find out.

Answer 6

I couldn't find a good answer for this either, so I decided to just replicate the message once the I start getting the cancel error. This is still in development but it basically changes the button callback to display the error alert rather than display the leader-board.

Just a note, not sure if this will be approved or not since I am replicating an Apple error message.

-(void) gcLogin: (id) sender {
    [[GKLocalPlayer localPlayer] authenticateWithCompletionHandler:^(NSError *error) {
        if(error) {
            if([[error domain] isEqualToString:GKErrorDomain] && [error code] == GKErrorCancelled) {
                [ResourceManager showAlertWithTitle:@"GameCenter Disabled" message:@"Sign in with Game Center application to enable"];
                mGameCenterCancelled = YES;
            }
            NSLog(@"%@", [error description]);
        } else { 
            [self updateMenu];
            mGameCenterCancelled = NO;
        }
    }];
}