小编Kir*_*kov的帖子

在离线模式下(例如,打开飞行模式),尝试找出在Game Center中使用成就的最佳方式.

据我所知,iOS 5+中的Game Center负责离线提交的成就和分数.它就像一个代理缓存,并在用户上线时将它们提交到在线游戏中心.考虑到这一点,我在做什么:

在用户身份验证成功时,我加载成就并将它们存储在字典中.

[GKAchievement loadAchievementsWithCompletionHandler:^(NSArray *gcAchievments, NSError *error)
{
    if (error) { ..skipped ..}
    //This dictionary will store current achievments, so that we didn't submit them
    //once more and didn't show notification.
    achievments = [[NSMutableDictionary alloc] initWithCapacity:gcAchievments.count];

    //Storing achievments in dictionary
    for(GKAchievement *a in gcAchievments)
        [achievments setObject:a forKey:a.identifier];       
}];

稍后当我提交新成就时,我会在字典中检查成就,如果成就已经完成,则不提交.如果我提交成就,我也会将其添加到achievments字典(内存中),以立即重新表明已经提交了此成就.

GKAchievement *cachedAchievment = [achievments objectForKey:identifier];
if (cachedAchievment && cachedAchievment.percentComplete >= 100)
{
    //Already unlocked this achievment.
    return;
}

GKAchievement *achievement = …