Swift NSSecureCoding 在解包時意外發現 nil

Question

我在 CoreData 中存儲了一個可轉換文件，並試圖使其符合 NSSecureCoding，但是當我嘗試解碼時，在解開可選值的同時意外發現 nil

在 XCDataModel 中，我將屬性設置為可轉換並使用自定義類 AssignedExerciseObjects，我還將轉換器設置為 AssignedExerciseObjectsValueTransformer

我還在我的 CoreData 堆棧中注冊了變壓器

這是我的變壓器的副本

@objc(AssignedExerciseObjectsValueTransformer)
final class AssignedExerciseObjectsValueTransformer: NSSecureUnarchiveFromDataTransformer {


static let name = NSValueTransformerName(rawValue: String(describing: AssignedExerciseObjectsValueTransformer.self))


override static var allowedTopLevelClasses: [AnyClass] {
    return [NSArray.self, AssignedExerciseObjects.self]
}

/// Registers the transformer.
public static func register() {
    let transformer = AssignedExerciseObjectsValueTransformer()
    ValueTransformer.setValueTransformer(transformer, forName: name)
}
}

這是我的自定義類的副本

import Foundation

public class AssignedExerciseObjects: NSObject, NSSecureCoding {

public static var supportsSecureCoding: Bool = true

public var assignedExerciseObjects: [AssignedExerciseObject] = []

enum Key:String {
    case assignedExerciseObjects = "assignedExerciseObjects"
}

init(assignedExerciseObjects: [AssignedExerciseObject]) {
    self.assignedExerciseObjects = assignedExerciseObjects
}

public func encode(with aCoder: NSCoder) {
    aCoder.encode(assignedExerciseObjects, forKey: Key.assignedExerciseObjects.rawValue)
}

public required convenience init?(coder aDecoder: NSCoder) {
    
    
    let mAssignedExerciseObjects = aDecoder.decodeObject(of: NSArray.self, forKey: Key.assignedExerciseObjects.rawValue) as! [AssignedExerciseObject]
 
   
    self.init(assignedExerciseObjects: mAssignedExerciseObjects)
}


}

public class AssignedExerciseObject: NSObject, NSSecureCoding {


public static var supportsSecureCoding: Bool = true




public var mainExercise: String = ""
public var prepareTime: String = ""
public var exerciseTime: String = ""
public var highIntensityTime: String = ""
public var restTime: String = ""

public var highLowSplit: Bool = false
public var isCompleted: Bool = false
public var isSkipped: Bool = false

public var order: Double = 0




enum Key:String {
    case mainExercise = "mainExercise"
    case prepareTime = "prepareTime"
    case exerciseTime = "exerciseTime"
    case highIntensityTime = "highIntensityTime"
    case restTime = "restTime"
    case highLowSplit = "highLowSplit"
    case isCompleted = "isCompleted"
    case isSkipped = "isSkipped"
    case order = "order"
}

init(mainExercise: String, prepareTime: String, exerciseTime: String, highIntensityTime: String, restTime: String, highLowSplit: Bool, isCompleted: Bool, isSkipped: Bool, order: Double) {
    self.mainExercise = mainExercise
    self.prepareTime = prepareTime
    self.exerciseTime = exerciseTime
    self.highIntensityTime = highIntensityTime
    self.restTime = restTime
    self.highLowSplit = highLowSplit
    self.isCompleted = isCompleted
    self.isSkipped = isSkipped
    self.order = order
}

public override init() {
    super.init()
}

public func encode(with aCoder: NSCoder) {
    
    aCoder.encode(mainExercise, forKey: Key.mainExercise.rawValue)
    aCoder.encode(prepareTime, forKey: Key.prepareTime.rawValue)
    aCoder.encode(exerciseTime, forKey: Key.exerciseTime.rawValue)
    aCoder.encode(highIntensityTime, forKey: Key.highIntensityTime.rawValue)
    aCoder.encode(restTime, forKey: Key.restTime.rawValue)
    aCoder.encode(highLowSplit, forKey: Key.highLowSplit.rawValue)
    aCoder.encode(isCompleted, forKey: Key.isCompleted.rawValue)
    aCoder.encode(isSkipped, forKey: Key.isSkipped.rawValue)
    aCoder.encode(order, forKey: Key.order.rawValue)
}

public required convenience init?(coder aDecoder: NSCoder) {
    
    let mMainExercise = aDecoder.decodeObject(of: NSString.self, forKey: Key.mainExercise.rawValue)! as String
    let mPrepareTime = aDecoder.decodeObject(of: NSString.self,forKey: Key.prepareTime.rawValue)! as String
    let mExerciseTime = aDecoder.decodeObject(of: NSString.self,forKey: Key.exerciseTime.rawValue)! as String
    let mHighIntensityTime = aDecoder.decodeObject(of: NSString.self,forKey: Key.highIntensityTime.rawValue)! as String
    let mRestTime = aDecoder.decodeObject(of: NSString.self,forKey: Key.restTime.rawValue)! as String
    let mHighLowSplit = aDecoder.decodeBool(forKey: Key.highLowSplit.rawValue)
    let mIsCompleted = aDecoder.decodeBool(forKey: Key.isCompleted.rawValue)
    let mIsSkipped = aDecoder.decodeBool(forKey: Key.isSkipped.rawValue)
    let mOrder = aDecoder.decodeDouble(forKey: Key.order.rawValue)
 
    self.init(mainExercise: String(mMainExercise), prepareTime:
                String(mPrepareTime), exerciseTime: String(mExerciseTime), highIntensityTime: String(mHighIntensityTime), restTime: String(mRestTime), highLowSplit: Bool(mHighLowSplit), isCompleted: Bool(mIsCompleted), isSkipped: Bool(mIsSkipped), order: Double(mOrder))
    
    }
}

這是它給我錯誤的地方

let mAssignedExerciseObjects = aDecoder.decodeObject(of: NSArray.self, forKey: Key.assignedExerciseObjects.rawValue) as! [AssignedExerciseObject]

我對 swift 還是很陌生，但我終生無法弄清楚為什么它返回 nil 值？

創建記錄后，似乎一切正常，但是當我嘗試在表中顯示記錄時，出現錯誤

任何幫助是極大的贊賞

問候

傑米

Answer 1

好的，我已經修好了

添加我的自定義類解決了這個問題

 let mAssignedExerciseObjects = aDecoder.decodeObject(of: [AssignedExerciseObject.self, NSArray.self], forKey: Key.assignedExerciseObjects.rawValue) as! [AssignedExerciseObject]