类没有初始化器错误领域类 Swift

Question

我得到一个 Class has no initializers 错误。这不是我设置课程的方式吗？这是一个领域对象数据库，我要存储的属性。我是 swift 和领域的新手，但我认为这就是它的完成方式。如果我取出 init() 函数并只分配它工作的所有值，但是诸如 justTook 之类的属性以及我不想以值开头的所有属性，我需要稍后在程序中设置它。

这是我的代码：

class MedInfo: Object {
    //  Info To Be Stored
    @objc dynamic var keyID = UUID().uuidString
    @objc dynamic var medName: String
    @objc dynamic var medDose: String
    @objc dynamic var currentDate: Date
    @objc dynamic var timeTook: Date
    @objc dynamic var lastTook: Date
    @objc dynamic var durationOfTime: Date
    @objc dynamic var doctorName: String
    @objc dynamic var rxDate: Date
    @objc dynamic var medInfo: String
    @objc dynamic var pictureOfMed: UIImage

    override static func primaryKey() -> String? {
        return "keyID"
    }

    convenience init(medName: String, medDose: String, currentDate: Date, timeTook: Date, lastTook: Date, durationOfTime: Date, doctorName: String,rxDate: Date, medInfo: String, pictureOfMed: UIImage) {
        self.medName = medName
        self.medDose = medDose
        self.currentDate = currentDate
        self.timeTook = timeTook
        self.lastTook = lastTook
        self.durationOfTime = durationOfTime
        self.doctorName = doctorName
        self.rxDate = rxDate
        self.medInfo = medInfo
        self.pictureOfMed = pictureOfMed
    }

Answer 1

您需要为所有参数设置默认值，如文档中模糊描述的那样。来自here：

在 Swift 中使用 Realm 时，Swift.reflect(_:) 函数用于 确定有关您的模型的信息，这需要调用 init() 成功。 这意味着所有非可选属性必须具有 默认值。

所有示例都显示了这一点，因此请遵循它们。因此应该声明你的类：

class MedInfo: Object {
    //  Info To Be Stored
    @objc dynamic var keyID = UUID().uuidString
    @objc dynamic var medName: String = ""
    @objc dynamic var medDose: String = ""
    @objc dynamic var currentDate: Date = Date()
    @objc dynamic var timeTook: Date = Date()
    @objc dynamic var lastTook: Date = Date()
    @objc dynamic var durationOfTime: Date = Date()
    @objc dynamic var doctorName: String = ""
    @objc dynamic var rxDate: Date = Date()
    @objc dynamic var medInfo: String = ""

    // UIImage not supported, you'll need to store a URL/filename or something else
    @objc dynamic var pictureOfMed: UIImage

Answer 2

您必须调用 init 来创建实例。

convenience init(medName: String, medDose: String, currentDate: Date, timeTook: Date, lastTook: Date, durationOfTime: Date, doctorName: String,rxDate: Date, medInfo: String, pictureOfMed: UIImage) {

    self.init() 

    self.medName = medName
    self.medDose = medDose
    self.currentDate = currentDate
    self.timeTook = timeTook
    self.lastTook = lastTook
    self.durationOfTime = durationOfTime
    self.doctorName = doctorName
    self.rxDate = rxDate
    self.medInfo = medInfo
    self.pictureOfMed = pictureOfMed
}

Answer 3

正如@ces 已经正确引用自 Realm 文档：“这意味着所有非可选属性都必须具有默认值。”

这就是为什么我认为创建 Realm 对象的最佳方法是将变量声明为可选项。

这样您就不必调用 init。这是我创建自己的 Realm 对象的方式，也是我见过的大多数人创建它们的方式。

所以你的对象应该是这样的：

class MedInfo: Object {
//  Info To Be Stored
@objc dynamic var keyID = UUID().uuidString
@objc dynamic var medName: String?
@objc dynamic var medDose: String?
@objc dynamic var currentDate: Date?
@objc dynamic var timeTook: Date?
@objc dynamic var lastTook: Date?
@objc dynamic var durationOfTime: Date?
@objc dynamic var doctorName: String?
@objc dynamic var rxDate: Date?
@objc dynamic var medInfo: String?
@objc dynamic var pictureOfMed: UIImage?

override static func primaryKey() -> String? {
    return "keyID"
}