使用可编码的对象

Question

我有一个应用程序，我尝试使用 UserDefaults 在本地保存 Codable 模型，但问题是 UserDefault 没有存储所有 values Model 并将 nil 分配给其中一些，有时分配正确的 value。所以我决定尝试另一种选择，即 realm 并且我能够修改我的 model 以使用 realm 但我有一个问题不是过程中的 解码 an Object 对象 使用领域。在使用 List 但非 array Objects[=45= 处理 Array object 时，我能够使其工作] 只是未能映射到JSON

下面是我正在处理的示例数组

{ "id": 732, "name": "Vendor Name", "logo": ".../thumb/missing.png", "kitchens": { "id": 36, "name": "Sandwiches" } }

型号class

class VendorsList : Object, Decodable { @objc dynamic var id : Int = 0 @objc dynamic var name : String? @objc dynamic var logo : String? // Create your Realm List. var kitchensList = List<VendorKitchens>() override class func primaryKey() -> String? { return "id" } private enum CodingKeys: String, CodingKey { case id case name case logo // Set JSON Object Key case kitchensList = "kitchens" } public required convenience init(from decoder: Decoder) throws { self.init() let container = try decoder.container(keyedBy: CodingKeys.self) self.id = try container.decode(Int.self, forKey: .id) self.name = try container.decode(String.self, forKey: .name) self.logo = try container.decode(String.self, forKey: .logo) // Map your JSON Array response let kitchens = try container.decodeIfPresent([VendorKitchens].self, forKey: .kitchensList) ?? [VendorKitchens()] kitchensList.append(objectsIn: kitchens) } } class VendorKitchens : Object, Decodable { @objc dynamic var id : Int = 0 @objc dynamic var name : String? override class func primaryKey() -> String? { return "id" } private enum CodingKeys: String, CodingKey { case id case name } }

这个returns一个错误

Failed to map data to JSON

Answer 1

来，试试这个。

class VendorsList : Object, Decodable {
    @objc dynamic var id : Int = 0
    @objc dynamic var name : String?
    @objc dynamic var logo : String?
    @objc dynamic var kitchens: VendorKitchens? = nil

    override class func primaryKey() -> String? {
        return "id"
    }

    private enum CodingKeys: String, CodingKey {
        case id
        case name
        case logo
        case kitchens = "kitchens"

    }

    public required convenience init(from decoder: Decoder) throws {
        self.init()
        let container = try decoder.container(keyedBy: CodingKeys.self)
        self.id = try container.decode(Int.self, forKey: .id)
        self.name = try container.decode(String.self, forKey: .name)
        self.logo = try container.decode(String.self, forKey: .logo)
        kitchens = try container.decodeIfPresent(VendorKitchens.self, forKey: .kitchensList)

    }

}


class VendorKitchens : Object, Decodable {
    @objc dynamic var id : Int = 0
    @objc dynamic var name : String?

    override class func primaryKey() -> String? {
        return "id"
    }

    private enum CodingKeys: String, CodingKey {
        case id
        case name
    }
}

使用可编码的对象

Using an Object with ream codable

realm

ios

swift

codable