我在玩新的wiftData,我正在试着理解关系是如何工作的,我很高兴有机会为类建模:
我的应用程序上的每个航班都包含许多机组人员,我编写了如下代码中的关系,但不断收到错误消息:致命错误:不存在反向关系
我们应该如何写这种关系:
@Model
class Flight {
@Attribute(.unique) var flightID: UUID
var typeOfFlight: String
var flightDateUTC : Date
var flightNumber: String?
@Relationship(.cascade) var flightData: FlightData
@Relationship(.cascade) var flightTime : FlightTime
@Relationship(.noAction) var aircraft : Aircraft?
@Relationship(inverse: \CrewModel.name)
var crews : [CrewModel]? //<-------------------------------
init(flightID: UUID, typeOfFlight: String, flightDateUTC: Date, flightNumber: String? = nil, flightData: FlightData, flightTime: FlightTime, aircraft: Aircraft? = nil, crews: [CrewModel]? = nil) {
self.flightID = flightID
self.typeOfFlight = typeOfFlight
self.flightDateUTC = flightDateUTC
self.flightNumber = flightNumber
self.flightData = flightData
self.flightTime = flightTime
self.aircraft = aircraft
self.crews = crews
}
}
@Model
class CrewModel{
@Attribute(.unique) var id: UUID = UUID()
@Relationship(.noAction, inverse: \Flight.flightID)
var name : String?
var crewID: String?
var company: String?
var isMe: Int?
var email: String?
var phone: String?
var score: Int?
var isPIC: Int?
var isSIC: Int?
var dataImage: Data?
var comment: String?
init(id: UUID, name: String? = nil, crewID: String? = nil, company: String? = nil, isMe: Int? = nil, email: String? = nil, phone: String? = nil, score: Int? = nil, isPIC: Int? = nil, isSIC: Int? = nil, dataImage: Data? = nil, comment: String? = nil) {
self.id = id
self.name = name
self.crewID = crewID
self.company = company
self.isMe = isMe
self.email = email
self.phone = phone
self.score = score
self.isPIC = isPIC
self.isSIC = isSIC
self.dataImage = dataImage
self.comment = comment
}
}