从符合 Decodable 协议的 class 派生的 class 会产生编译器错误“Class 'CardListResponse' 没有初始化程序”

Question

public struct CodeAndDetails: Codable {
    public let html: String
    public var code: String

    private enum CodingKeys: String, CodingKey {
        case html = "DETAILS", code = "CODE"
    }

    public func getMessage(font: UIFont) -> NSAttributedString? {
        let res = NSAttributedString(html: html, font: font)
        return res
    }
}

public class BaseResponse: Decodable {

    enum CodingKeys: String, CodingKey {
        case successDetails = "Success"
    }
    public let successDetails: [CodeAndDetails]
}

此处：

public class CardListResponse: BaseResponse {
    public let cards: [DebitCard]?
    public let activeCardId: Int?

    enum CodingKeys: String, CodingKey {
        case cards = "row"
        case activeCardId = "CurrentActiveId"
    }
}

我得到：

Class 'CardListResponse' has no initializers

我有什么选择来处理这个 swift 自负？

问题转移到了运行时。妹子问题在这里：

Answer 1

您应该将 CardListResponse 属性设置为 var 而不是 let

let 是常量，这意味着您无法更改值

你能做什么？

您可以将默认值设置为 cards 和 activeCardId 属性，例如：

public class CardListResponse: BaseResponse {
    public let cards: [DebitCard]? = nil
    public let activeCardId: Int? = nil

    enum CodingKeys: String, CodingKey {
        case cards = "row"
        case activeCardId = "CurrentActiveId"
    }
}

或

您可以将 let 更改为 var，例如：

public class CardListResponse: BaseResponse {
    public var cards: [DebitCard]?
    public var activeCardId: Int?

    enum CodingKeys: String, CodingKey {
        case cards = "row"
        case activeCardId = "CurrentActiveId"
    }
}

希望一切顺利。

尽情享受吧。

从符合 Decodable 协议的 class 派生的 class 会产生编译器错误“Class 'CardListResponse' 没有初始化程序”

a class derived from a class compliant with Decodable protocol yields a compiler error 'Class 'CardListResponse' has no initializers'

decodable

swift5