检索最佳得分游戏中心Swift

我遇到麻烦了，我无法修复与func相关的错误，以便从游戏中心检索最佳分数。如果你有分数，这个函数运行得很好，但是如果用户没有分数，它就会崩溃

有什么建议吗？代码如下：

func retrieveBestScore() {
        if GKLocalPlayer.localPlayer().isAuthenticated {

            // Initialize the leaderboard for the current local player
            var gkLeaderboard = GKLeaderboard(players: [GKLocalPlayer.localPlayer()])
            gkLeaderboard.identifier = leaderboardID
            gkLeaderboard.timeScope = GKLeaderboardTimeScope.allTime

            // Load the scores
            gkLeaderboard.loadScores(completionHandler: { (scores, error) -> Void in

                // Get current score
                var currentScore: Int64 = 0
                if error == nil {
                    if (scores?.count)! > 0 {
                        currentScore = (scores![0] ).value
                        //We also want to show the best score of the user on the main screen
                        if self.language.contains("it"){
                            self.labelBestScore.text = "Miglior Punteggio: " + String(currentScore)
                            self.bestScore = Int(currentScore)
                        }else{
                            self.labelBestScore.text = "Your Best Score: " + String(currentScore)
                            self.bestScore = Int(currentScore)
                        }
                        print("Punteggio attuale",currentScore)
                    }
                }

            })
        }
    }

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谢谢大家!

根据您的代码，由于强制展开“分数”数组，您可能会遇到此问题

在结束语中尝试以下内容：

var currentScore: Int64 = 0
if error == nil, let scores = scores {
    if scores.count > 0 {
        currentScore = scores[0].value
        //We also want to show the best score of the user on the main screen
        if self.language.contains("it"){
            self.labelBestScore.text = "Miglior Punteggio: " + String(currentScore)
            self.bestScore = Int(currentScore)
        }else{
            self.labelBestScore.text = "Your Best Score: " + String(currentScore)
            self.bestScore = Int(currentScore)
        }
        print("Punteggio attuale",currentScore)
    }
}

这里有一种第二种方法，它可以进一步压缩您的代码，我认为这应该也可以，但是如果没有看到更多的代码，很难确定，它可能需要一些小的更改

guard error == nil, let scores = scores, let currentScore = scores.first?.value else {
    print("GameCenter error or no scores: \(String(describing: error)))")
    return
}

//We also want to show the best score of the user on the main screen
if self.language.contains("it"){
    self.labelBestScore.text = "Miglior Punteggio: " + String(currentScore)
    self.bestScore = Int(currentScore)
}else{
    self.labelBestScore.text = "Your Best Score: " + String(currentScore)
    self.bestScore = Int(currentScore)
}
print("Punteggio attuale",currentScore)

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你能把错误回溯包括进来吗？它在第行的“error”中返回“nil”：if error==nil{…}真棒！如果你能把它标出来，那就太好了。我还将使用另一种方法进行更新，也可以使用guard语句进行更新。