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arrays - 快速更新数组的元素值

问题描述

我有很多使用 Matlab 的经验，但我最近才开始使用 Swift 4 进行编程。我目前的项目涉及构建问卷。我使用 Xcode 中的“拖放”功能为情节提要中的按钮生成 @IBAction 函数，这会导致按下的按钮改变其外观。此功能包含在下面代码片段中的 ButtonResponse 类中：

    struct ResponseProfile {

       var responseArray: Array<String>
       init(responseArray: Array<String>) {
            self.responseArray = ["unchecked","unchecked","unchecked","unchecked","unchecked","unchecked","unchecked"]
        }

        mutating func updateArray(_ anArray: Array<String>) -> (Array<String>) {
            responseArray = anArray
            return responseArray
        }

    }

    class ButtonResponse: UIButton {

        var responseVariables: ResponseProfile

        var checkedImage = UIImage(named: "checkedResponseBox")! as UIImage
        var uncheckedImage = UIImage(named: "uncheckedResponseBox")! as UIImage

        required init?(coder aDecoder: NSCoder) {
            self.responseVariables = ResponseProfile(
                responseArray: []
            )
            super.init(coder: aDecoder)
        }


        @IBAction func checkboxTapped(_ sender: UIButton) {
            switch sender.accessibilityIdentifier {
                case "excellent":

                    let oldResponseStatus = responseVariables.responseArray[0]
                    if oldResponseStatus == "unchecked"{
                        sender.setImage(checkedImage, for: UIControlState.normal)
                        let oldResponsePresence = responseVariables.responseArray.contains("checked")

                        if oldResponsePresence == true {
                            responseVariables.responseArray = ["unchecked","unchecked","unchecked","unchecked","unchecked","unchecked","unchecked"]
                        }
                        responseVariables.responseArray[0] = "checked"
                    } else if oldResponseStatus == "checked" {
                        sender.setImage(uncheckedImage, for: UIControlState.normal)
                        responseVariables.responseArray[0] = "unchecked"
                }

                case "veryGood":
                    let oldResponseStatus = responseVariables.responseArray[1]
                    if oldResponseStatus == "unchecked" {
                        sender.setImage(checkedImage, for: UIControlState.normal)
                        let oldResponsePresence = responseVariables.responseArray.contains("checked")
                        if oldResponsePresence == true {
                            responseVariables.responseArray = ["unchecked","unchecked","unchecked","unchecked","unchecked","unchecked","unchecked"]
                        }
                        responseVariables.responseArray[1] = "checked"
                    } else if oldResponseStatus == "checked" {
                        sender.setImage(uncheckedImage, for: UIControlState.normal)
                        responseVariables.responseArray[1] = "unchecked"
                    }

                default: break

            }
        }

    }

我想我可以使用一个数组在内部表示用户界面中按钮的状态（这将是“responseArray”变量）。通过在按下按钮后更改 responseArray 中的元素，我认为我可以跟踪按下了哪些按钮，并确保一次检查的按钮不超过一个。我错误地认为 responseArray 会被更新，但事实并非如此。阵列总是恢复到其初始状态。

NB responseArray 包含七个元素，因为有七个响应选项。到目前为止，我只尝试对两个响应选项进行编程：“优秀”和“非常好”。

在试图找到解决方案时，我试图在操场上简化上述代码：

import UIKit

    struct ResponseProfile {
        var responseArray: Array<String>
        init(responseArray: Array<String>) {
            self.responseArray =     ["unchecked","unchecked","unchecked","unchecked","unchecked","unchecked","unchecked"]
        }
        mutating func updateArray(input anArray: Array<String>) -> (Array<String>) {
            responseArray = anArray
            return responseArray
        }
    }

    class ButtonResponse {
        var responseVariables: ResponseProfile
        init(){
            self.responseVariables = ResponseProfile(responseArray: [])
        }
        var responseA = ResponseProfile(responseArray: [])

    }

    var responseOne = ResponseProfile(responseArray: [])
    responseOne.responseArray[0] = "checked" //user performs action resulting in first element being changed from a starting value of "unchecked" to "checked"
    responseOne.updateArray(input: responseOne.responseArray)

    var responseTwo = ResponseProfile(responseArray:[])
    responseTwo.responseArray //responseArray revert to initialization values. How can I keep changes to the responseArray?

如何在 ResponseProfile 结构中更新 responseArray 而无需创建新变量来记录每次更改？这是我应该考虑的问题，还是在更一般的层面上，我应该采取更好的策略？

我很惊讶我为处理这个问题付出了这么多努力。我认为如果我阅读文档的相关部分并研究一些示例代码，答案就会很清楚。我发现的所有示例代码都过于简单，只关注更新数组的一次迭代。

任何意见或建议将不胜感激！

标签： arraysswift

解决方案

感谢您的回复巴文。通过将 responseArray 通过引用（如 Bhavin 建议）传递给必要的类（结果是 ButtonResponse 类而不是 ResponseProfile），我可以给 responseArray 一个初始值。然后我使用 buttonPress 函数来更新 responseArray。见下文：

class ButtonResponse: Responses {
var responseArray: [String]
init (responseArray: [String]) {
    self.responseArray = responseArray
}

func buttonPress(inputString: String, targetIndex: Int) -> [String] {
    //need guard statement to block function when targetIndex > number of elements in responseArray
    responseArray[targetIndex] = inputString
    return responseArray
}
}

let initiateResponseArray = 

["unchecked","unchecked","unchecked","unchecked","unchecked","unchecked","unchecked"]
var doPress = ButtonResponse(responseArray: initiateResponseArray)
doPress.buttonPress(inputString: "checked", targetIndex: 0)
var getPressInfo1 = doPress.responseArray
print(getPressInfo1)
//prints: ["checked", "unchecked", "unchecked", "unchecked", "unchecked", "unchecked", "unchecked"]
doPress.buttonPress(inputString: "checked", targetIndex: 1)
var getPressInfo2 = doPress.responseArray
print(getPressInfo2)
//prints: ["checked", "checked", "unchecked", "unchecked", "unchecked", "unchecked", "unchecked"]

我仍然不确定如何在我正在从事的项目中实施此解决方案。我将为此创建一个单独的问题，因为它似乎引发了不同的问题。

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