swift - 我需要帮助调试此错误 - child 数学测验

Question

我的学校项目是一个 child 数学游戏，测试他们的加法、减法和乘法。我有两个与该错误相关的 VC。我一直遇到的错误是，每次我选择任何选项时，它都会忽略所有其他操作并遵循乘法指令!我已经尝试了一切，但我对这个应用程序感到沮丧。

选项_VC

class Option_VC: UIViewController {

var addition_true: Bool = false
var subtract_true: Bool = false
var multiply_true: Bool = false

override func viewDidLoad() {
    super.viewDidLoad()

    // Do any additional setup after loading the view.
}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}


override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
    if addition_true == true {
        let nextVC: Quiz_VC = segue.destinationViewController as! Quiz_VC
        nextVC.addition_true = true
    }else if subtract_true == true {
        let nextVC: Quiz_VC = segue.destinationViewController as! Quiz_VC
        nextVC.subtract_true = true
    }else {
        let nextVC: Quiz_VC = segue.destinationViewController as! Quiz_VC
        nextVC.multiply_true = true
    }
}

@IBAction func addition_enter(sender: AnyObject) {
    addition_true = true
    multiply_true = false
    subtract_true = false
}

@IBAction func subtract_enter(sender: AnyObject) {
    subtract_true = true
    addition_true = false
    multiply_true = false
}

@IBAction func multiply_enter(sender: AnyObject) {
    multiply_true = true
    addition_true = false
    subtract_true = false
}

}

测验_VC

class Quiz_VC: UIViewController {

@IBOutlet var n1_lbl: UILabel!
@IBOutlet var back: UIButton!
@IBOutlet var next: UIButton!
@IBOutlet var enter: UIButton!
@IBOutlet var answer_field: UITextField!
@IBOutlet var symbol_lbl: UILabel!
@IBOutlet var n2_lbl: UILabel!
@IBOutlet var comment_lbl: UILabel!
@IBOutlet var score_lbl: UILabel!
var addition_true: Bool = false
var subtract_true: Bool = false
var multiply_true: Bool = false
var enter_entered_true: Bool = false
var answer: UInt32 = 0
var finalanswer: UInt32 = 0
var n1: UInt32 = 0
var n2: UInt32 = 0
var count = 0
var score = 0
var temp: UInt32 = 0
var operation: String = ""


override func viewDidLoad() {
    super.viewDidLoad()
    back.hidden = true
    next.hidden = true
    if addition_true == true {
        AdditionQuestions()
    }else if subtract_true == true {
        SubtractionQuestions()
    }
    if multiply_true == true && addition_true == false && subtract_true == false{
        MultiplicationQuestions()
    }
}

func Operation() {
    if addition_true == true {
        operation = "1"
    }else if subtract_true == true {
        operation = "2"
    }else  {
        operation = "3"
    }

    switch operation {
    case "1":
        finalanswer = n1 + n2
    case "2":
        finalanswer = n1 - n2
    case "3":
        finalanswer = n1 * n2
    default: break
    }
}

func AdditionQuestions() {
    n1 = arc4random_uniform(9)+1
    n2 = arc4random_uniform(9)+1
    n1_lbl.text = "\(n1)"
    n2_lbl.text = "\(n2)"
    symbol_lbl.text = "+"
    score_lbl.text = ""
    comment_lbl.text = ""
}

func SubtractionQuestions() {
    n1 = arc4random_uniform(9)+1
    n2 = arc4random_uniform(9)+1
    symbol_lbl.text = "-"
    if n2 > n1 {
        temp = n1
        n1 = n2
        n2 = temp
    }
    n1_lbl.text = "\(n1)"
    n2_lbl.text = "\(n2)"
}

func MultiplicationQuestions() {
    n1 = arc4random_uniform(9)+1
    n2 = arc4random_uniform(9)+1
    symbol_lbl.text = "×"
    n1_lbl.text = "\(n1)"
    n2_lbl.text = "\(n2)"
}

func EndQuiz() {
    if count > 3 {
        enter.hidden = true
        next.hidden = true
        back.hidden = false
        score_lbl.text = "Score: \(score)"
        comment_lbl.text = "Completed Quiz"
    }
}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}

@IBAction func enter_entered(sender: AnyObject) {
    if answer_field.text != nil {
        enter_entered_true = true
        answer = UInt32(answer_field.text!)!
        count = count + 1
        Operation()
        if answer != finalanswer {
            comment_lbl.text = "Incorrect"
        } else {
            comment_lbl.text = "Correct"
            score = score + 1
        }
    } else {
        comment_lbl.text = "Enter a number!"
    }
    enter.hidden = true
    next.hidden = false
}

@IBAction func next_entered(sender: AnyObject) {
    if addition_true == true {
        AdditionQuestions()
        comment_lbl.text = ""
    }else if subtract_true == true {
        SubtractionQuestions()
        comment_lbl.text = ""
    }
    if multiply_true == true && addition_true == false && subtract_true == false{
        MultiplicationQuestions()
        comment_lbl.text = ""
    }
    enter.hidden = false
    next.hidden = true
    EndQuiz()
}

}

Answer 1

当您点击其中一个按钮(加、减或乘)时，应用程序会立即执行 prepareForSegue，然后再执行与这些按钮相关的操作。因此，addition_true、subtraction_true 和 multiplication_true 都始终为 false，并且代码会进入 else 子句，该子句设置乘法选项。

要解决这个问题:

1. 在 Storyboard中删除三个按钮的转场。
2. 添加从第一个 View Controller 到第二个 View Controller 的 Segue(控制从第一个 View Controller 顶部的黄色圆圈拖动到第二个 View Controller 的主体)。
3. 给segue一个名称(突出显示segue并在属性检查器中将其命名(“mainSegue”或其他名称))

4. 在您的代码中，将以下行添加到三个操作(addition_enter 等)中每个操作的末尾:

   performSegueWithIdentifier("mainSegue", 发件人: self)

这将确保在执行按钮操作后调用 segue。