Swift/当用户得到正确答案时，如何每次得分增加一分

Question

我是Swift的新手。我目前正在学习结构模块。

我被要求创建一个分数，每次用户答对答案时增加1分，但我的分数最终增加了2分。我很困惑。其他一切都很好。有人能帮我吗？

我的代码如下：

import UIKit
class ViewController: UIViewController {
@IBOutlet weak var questionLable: UILabel!
@IBOutlet weak var progressBar: UIProgressView!
@IBOutlet weak var trueButton: UIButton!
@IBOutlet weak var falseButton: UIButton!
@IBOutlet weak var scoreLabel: UILabel!
var quizBrain = QuizBrain()

override func viewDidLoad() {
super.viewDidLoad()
progressBar.progress = 0
updatedUI()
}

@IBAction func answerButtonPressed(_ sender: UIButton) {
let userAnswer = sender.currentTitle!        
let userGotItRight = quizBrain.checkAnswer(userAnswer) 
print(quizBrain.checkAnswer(userAnswer))
if userGotItRight{              
UIView.animate(withDuration: 0.2) {
sender.backgroundColor = #colorLiteral(red: 0.4745098054, green: 0.8392156959, blue: 0.9764705896, alpha: 1)
}
UIView.animate(withDuration: 0.2) {
sender.backgroundColor = UIColor.clear
}
}else{
UIView.animate(withDuration: 0.2) {
sender.backgroundColor = #colorLiteral(red: 0.9098039269, green: 0.4784313738, blue: 0.6431372762, alpha: 1)
}
UIView.animate(withDuration: 0.2) {
sender.backgroundColor = UIColor.clear
}
}
quizBrain.nextQuestion()
updatedUI()
}
func updatedUI()  {
questionLable.text = quizBrain.getQuestionText()
scoreLabel.text = "Score:(quizBrain.getScore())"
progressBar.progress = quizBrain.getProgress()
}
}

下一部分是型号：

import Foundation
struct QuizBrain {
let quiz = [
Question(q: "A slug's blood is green.", a: "True"),
Question(q: "Approximately one quarter of human bones are in the feet.", a: "True"),
Question(q: "The total surface area of two human lungs is approximately 70 square metres.", a: "True"),
Question(q: "Chocolate affects a dog's heart and nervous system; a few ounces are enough to kill a small dog.", a: "True")
]
var questionNumber = 0
var score = 0
mutating func checkAnswer(_ userAnswer: String) -> Bool {
if userAnswer == quiz[questionNumber].answer{     
score += 1
return true                 
}else{
return false
}
}
mutating func getScore() -> Int {
return score
}
func getQuestionText() -> String {
return quiz[questionNumber].text     
}
func getProgress() -> Float {
let progress = Float(questionNumber + 1)/Float(quiz.count)
return progress
}
mutating func nextQuestion(){
if questionNumber + 1 < quiz.count{           
questionNumber += 1       
}else {
questionNumber = 0
score = 0
}
}
}

Answer 1

您的问题在于以下两行：

let userGotItRight = quizBrain.checkAnswer(userAnswer) 
print(quizBrain.checkAnswer(userAnswer))

在第一行中，你检查答案，看看它是否属实。如果为true，它会增加一，但在下一行中，您只想打印结果，但实际上您再次调用checkAnswer，这会使它增加一次。

也许你可以把这两行改成这样：

let userGotItRight = quizBrain.checkAnswer(userAnswer) 
print(userGotItRight)