使用以下代码，GKLocalPlayer().authenticated 变量始终为 false。一旦代码运行到 “User still not authenticated”，您就可以下载 Game Center 数据。这是错误还是以下代码的问题？

func notificationReceived()
{
    println("GKPlayerAuthenticationDidChangeNotificationName - Authentication Status: \(self.localPlayer.authenticated)")
}

//MARK: 2 Authenticate the Player
func authenticateLocalPlayer()
{
    println(__FUNCTION__)
    self.delegate?.willSignIn()

    self.localPlayer.authenticateHandler = {(viewController : UIViewController!, error : NSError!) -> Void in

        if (viewController != nil)
        {
            dispatch_async(dispatch_get_main_queue(), {
                self.showAuthenticationDialogueWhenReasonable(viewController)
                })
        }

        else if (self.localPlayer.authenticated == true)
        {
                println("Player is Authenticated")
                self.registerListener()
                self.downloadCachedMatches()
                self.delegate?.didSignIn()
        }

        else
        {
            println("User Still Not Authenticated")
            self.delegate?.failedToSignIn()
        }

        if (error)
        {
            self.delegate?.failedToSignInWithError(error)
        }
    }
}

//MARK: 2a Show Authentication Dialogue
func showAuthenticationDialogueWhenReasonable(viewController:UIViewController!) -> Void
{
    println(__FUNCTION__)
    UIApplication.sharedApplication().keyWindow.rootViewController.presentViewController(viewController, animated: true, completion: nil)
}

控制台输出如下所示:

    init(notification:)
    authenticationCheck()
    authenticateLocalPlayer()
    GKPlayerAuthenticationDidChangeNotificationName - Authentication Status: false
    GKPlayerAuthenticationDidChangeNotificationName - Authentication Status: false
    showAuthenticationDialogueWhenReasonable
    GKPlayerAuthenticationDidChangeNotificationName - Authentication Status: false
    GKPlayerAuthenticationDidChangeNotificationName - Authentication Status: false
    GKPlayerAuthenticationDidChangeNotificationName - Authentication Status: false
    User Still Not Authenticated
    Aug  2 07:33:10 iMac.local   <Debug>: 07:33:10.149128 com.apple.viceroytrace: ENV: VRTraceLogToFile="-"
    Aug  2 07:33:10 iMac.local   <Debug>: 07:33:10.149544 com.apple.viceroytrace: ENV: VRTraceErrorLogLevel="ALL"
    Aug  2 07:33:10 iMac.local   <Debug>: 07:33:10.149997 com.apple.viceroytrace: ENV: VRTraceMonitorNSLog="1"
    Aug  2 07:33:10 iMac.local   <Debug>: 07:33:10.150429 com.apple.viceroytrace: ENV: VRTraceStreamOutputFormat="CSV"
    Aug  2 07:33:10 iMac.local   <Debug>: 07:33:10.150875 com.apple.viceroytrace: ENV: VRTraceLogToFile="-"
    Aug  2 07:33:10 iMac.local   <Debug>: 07:33:10.151312 com.apple.viceroytrace: ENV: VRTraceErrorLogLevel="ALL"
    Aug  2 07:33:10 iMac.local   <Debug>: 07:33:10.151768 com.apple.viceroytrace: ENV: VRTraceMonitorNSLog="1"
    Aug  2 07:33:10 iMac.local   <Debug>: 07:33:10.152211 com.apple.viceroytrace: ENV: VRTraceStreamOutputFormat="CSV"
    Aug  2 07:33:10 iMac.local   <Debug>: 07:33:10.152626 com.apple.viceroytrace: ENV: VRTraceLogToFile="-"
    Aug  2 07:33:10 iMac.local   <Debug>: 07:33:10.153060 com.apple.viceroytrace: ENV: VRTraceErrorLogLevel="ALL"
    Aug  2 07:33:10 iMac.local   <Debug>: 07:33:10.153489 com.apple.viceroytrace: ENV: VRTraceMonitorNSLog="1"
    Aug  2 07:33:10 iMac.local   <Debug>: 07:33:10.153925 com.apple.viceroytrace: ENV: VRTraceStreamOutputFormat="CSV"
    Aug  2 07:33:10 iMac.local   <Info>: 07:33:10.154140 com.apple.viceroytrace: [CHECKPOINT] logging-started
    Aug  2 07:33:10 iMac.local   <Notice>: 07:33:10.154146 com.apple.viceroytrace: gVRTraceErrorLogLevel initialized to ALL (9)
    Aug  2 07:33:10 iMac.local   <Info>: 07:33:10.144097 com.apple.AVConference: GKSConnSettings: set server: {
        "gk-cdx" = "17.173.254.218:4398";
        "gk-commnat-cohort" = "17.173.254.220:16386";
        "gk-commnat-main0" = "17.173.254.219:16384";
        "gk-commnat-main1" = "17.173.254.219:16385";
    }

最佳答案

如果您尝试翻译 Game Center 编程指南中的 Objective-C 代码:“Authenticating a Local Player” ->

( https://developer.apple.com/library/ios/documentation/NetworkingInternet/Conceptual/GameKit_Guide/Users/Users.html#//apple_ref/doc/uid/TP40008304-CH8-SW18 )

...那么你没有完全正确地遵循模式

你在哪里使用:

if (viewController) {
    ...
} else {
    if (localPlayer.authenticated) {
        ...
    } else {
        ...
    }
}

...他们的模式使用:

if (viewController) {
    ...
} else if (localPlayer.authenticated) {
    ...
} else {
    ...
}

尝试使用他们的模式重写您的代码——需要注意的重要事项是他们写的地方:

Game Kit 会自动异步验证玩家身份，并在必要时调用您的身份验证处理程序来完成该过程。

...他们没有具体说明何时或多少次他们尝试进行身份验证 -无论如何这一切都是异步发生的，我完全可以想象你的代码可能会以当前形式打印到控制台“用户仍未通过身份验证”，但是当你的应用程序的其他部分检查时他们可能已经通过身份验证并能够下载 Game Center 数据。

还有一点要注意:您也可能会看到缓存了 Game Center 数据的情况...请注意，在示例的条件分支的最后 else 中( if...else if...else), 他们完全禁用 Game Center

让我知道结果如何!我很想知道

关于authentication - 使用 Swift 进行游戏中心身份验证，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/25007235/