swift - 解码 RealmSwift 类中的可选对象列表

Question

我正在尝试在 Realm 类中初始化 Codable 对象列表，问题是当服务器返回空列表时应用程序崩溃

这是初始化List的代码

class TicketDetails: Object, Decodable {

    var working: [WorkingHour]?
    var workingHours = List<WorkingHour>()

    public convenience required init(from decoder: Decoder) throws {
        self.init()
        let container = try decoder.container(keyedBy: CodingKeys.self)
        if let workingArray = try container.decodeIfPresent(Array<WorkingHour>.self, forKey: .working) {
            working = workingArray
            workingHours.append(objectsIn: workingArray)
        } else {
            working = nil
            workingHours = List.init()
        }
    }
}

Answer 1

这里有一些奇怪的地方。

TicketDetails 被声明为 Realm 对象，但包含一个数组，它只是 Realm List 属性的副本。为什么？删除阵列。 List 需要是一个 let，并删除整个 else 子句，因为那将不起作用。

class TicketDetails: Object, Decodable 
{
  let workingHours = List<WorkingHour>()

  public convenience required init(from decoder: Decoder) throws {
    self.init()
    let container = try decoder.container(keyedBy: CodingKeys.self)
    if let workingArray = try container.decodeIfPresent(Array<WorkingHour>.self, forKey: .working) 
    {
        workingHours.append(objectsIn: workingArray)
    }
  }
}