如何在测验游戏中节省用户进度

Question

我想知道如何在测验游戏中节省用户进度。每当用户关闭其重置应用程序时。这是我的代码：

import UIKit
import GoogleMobileAds
class ViewController: UIViewController, GADBannerViewDelegate {
    //Place your instance variables here
    let allQuestions = QuestionBank()
    var pickedAnswer : Bool = false
    var questionNumber : Int = 0
    var score : Int = 0
    let googleAdTestID: String = "ca-app-pub-3940256099942544/2934735716"
    @IBOutlet weak var questionLabel: UILabel!
    @IBOutlet weak var scoreLabel: UILabel!
    @IBOutlet weak var bannerView: GADBannerView!
    @IBOutlet weak var progressLabel: UILabel!
    override func viewDidLoad() {
        super.viewDidLoad()
        print("Google Mobile Ads SDK version: " + GADRequest.sdkVersion() )
        bannerView.adUnitID = googleAdTestID
        bannerView.rootViewController = self
        bannerView.load(GADRequest())
        nextQuestion()
    }
    @IBAction func skipButton(_ sender: Any) {
        skip()
    }
    func skip() {
        if score <= 4 {
        }
        else if score >= 5 {
            questionNumber = questionNumber + 1
            nextQuestion()
            score = score - 5
            scoreLabel.text = "Coins: (score)"
        }
    }
    @IBAction func answerPressed(_ sender: AnyObject) {
        if sender.tag == 1 {
            pickedAnswer = true
        }
        else if sender.tag == 2 {
            pickedAnswer = false
        }
        checkAnswer()
        questionNumber = questionNumber + 1
        nextQuestion()
    }
    func updateUI() {
        scoreLabel.text = "Coins: (score)"
        progressLabel.text = "Question Number: (questionNumber + 1)"
    }
    func nextQuestion() {
        if questionNumber <= 37 {
            questionLabel.text = allQuestions.list[questionNumber].questionText
            updateUI()
        }
        else {
            let alert = UIAlertController(title: "Awesome", message: "You have finished all the questions!! Do you want to start over?", preferredStyle: .alert)
            let restartAction = UIAlertAction(title: "Restart", style: .default, handler: { (UIAlertAction) in
                self.startOver()
            })
            alert.addAction(restartAction)
            present(alert, animated: true, completion: nil)
        }
    }
    func checkAnswer() {
        let correctAnswer = allQuestions.list[questionNumber].answer
        if correctAnswer == pickedAnswer {
            print("Correct!")
            ProgressHUD.showSuccess("Correct!!")
            // varible += 1 same as varible = varible + 1
            score += 1
        }
        else {
            print("wrong!")
            ProgressHUD.showError("Wrong!!")
        }
    }
    func startOver() {
        questionNumber = 0
        nextQuestion()
        score = 0
        scoreLabel.text = "Score: 0"
    }
}

Answer 1

保存

// save necessory information using UserDefaults
// Add this code at your business logic
let database = UserDefaults.standard
let questionNumber = 2
database.set(questionNumber, forKey: "LAST_ANSWERED_QUESTION_NUMBER")
let score = 23
database.set(score, forKey: "QUIZ_SCORE")
let sync = database.synchronize()
if sync{
    print("userdefaults - sync done")
}else{
    print("userdefaults - failed to sync")
}

提取

//access stored values from UserDefaults
// Add this code at your business logic
let database = UserDefaults.standard
if let lastAnswredQuestion = database.value(forKey: "LAST_ANSWERED_QUESTION_NUMBER") as? Int{
    print("LAST_ANSWERED_QUESTION_NUMBER (lastAnswredQuestion)")
}
if let scored = database.value(forKey: "QUIZ_SCORE") as? Int{
    print("QUIZ_SCORE (scored)")
}

注意：数据将存储在安装应用程序之前，如果用户删除应用程序，则整个数据将从UserDefaults中消失。