带有持久数据的排行榜，使用用户默认保存值

Question

我正在尝试创建排行榜，但玩家姓名和分数并未永久保存，“排行榜”仅包含来自文本视图中最新游戏的数据。我尝试使arrayOfData最初持有playerName和finalScore而不是一个空数组，但问题仍然存在。如何在排行榜中永久显示playerName和playerScore，并在更多人玩的时候添加更多名称和分数？

var finalScore = Int()
var playerName = String()
var allMyStoredData = UserDefaults.standard
var arrayOfData: [Any] = []
class secondVC: UIViewController {

@IBOutlet weak var scoreLabel: UILabel!
@IBOutlet weak var nameTF: UITextField!
@IBOutlet weak var doneButton: UIButton!
var playerScore = 0
var arrayOfData: [Any] = []
    override func viewDidLoad() {
    super.viewDidLoad()
        scoreLabel.text = "Your score is: \(finalScore)"
        loadData()
}

@IBAction func donePressed(_ sender: Any) {
    saveData()
    performSegue(withIdentifier: "toLeaderboard", sender: self)
}

func saveData () {
    playerName = nameTF.text!
    playerScore = finalScore
    arrayOfData.append(playerName)
    arrayOfData.append(playerScore)
    allMyStoredData.set(playerName, forKey: "saveTheName")
    allMyStoredData.set(playerScore, forKey: "saveTheScore")
    allMyStoredData.set(arrayOfData, forKey: "saveTheArray")


}

func loadData () {
    if let loadPlayerName:String = UserDefaults.standard.value(forKey: "saveTheName") as? String {
        playerName = loadPlayerName
    }

    if let loadTheScore:Int = UserDefaults.standard.value(forKey: "saveTheName") as? Int {
        playerScore = loadTheScore
    }
}

}

//这是排行榜视图控制器中的代码

class leaderboardViewController: UIViewController {

    @IBOutlet weak var theTextView: UITextView!
    override func viewDidLoad() {
        super.viewDidLoad()
        theTextView.text = "\((arrayOfData).map{"\($0)"}.joined(separator: "          Score: "))"
    }

}

Answer 1

您每次使用新阵列覆盖saveTheArray项目UserDefaults。

您想先获取已保存的数组，附加新游戏数据，然后重新保存：

//Create user defaults instance
let userDefaults = UserDefaults.standard

//User defaults key
let historicalGameDataKey = "historicalGameData"

//Fetch game data array
var historicalGameData = userDefaults.array(forKey: historicalGameDataKey)

//Create array if it is nil (i.e. very first game)
if historicalGameData == nil {
    historicalGameData = []
}

//Create game data dictionary
let gameData = [
    "playerName": playerName,
    "playerScore": playerScore
]

//Append game data dictionary to the array
historicalGameData?.append(["playerName": gameData])

//Save the updated array
userDefaults.set(historicalGameData, forKey: historicalGameDataKey

核心数据是存储此数据的更好方法，但此示例应使用UserDefaults解决您的问题。