-1
我在嘗試使用NSCoding保存/存檔對象時遇到了一些問題。我基本上有一個類QA,它定義了一個問題和答案,我也有一個類Volume,它包含幾個屬性,包括一個QA對象數組。使用NSCoding保存對象時出現異常Swift
調用NSKeyedArchiver.archiveRootObject方法時發生此錯誤。我懷疑它是與QA對象數組有關的,因爲如果我註釋掉那部分,則不拋出異常。
我的卷類繼承自NSObject和NSCoding,並且QA對象只從NSObject繼承。
引發的異常是:... encodeWithCoder:]:0x600000077c80
的方法被用來存檔發送到實例無法識別選擇 是:
static func save() {
print("starting save...")
let DocumentsDirectory = FileManager().urls(for: .documentDirectory, in: .userDomainMask).first!
let ArchiveURL = DocumentsDirectory.appendingPathComponent("volumesData")
NSKeyedArchiver.archiveRootObject(VolumeTableViewController.volumesArray, toFile: ArchiveURL.path)
print("Ending save...")
}
我的卷類:
import Foundation
class Volume: NSObject, NSCoding {
let volumeNumber: Int
var completed: Bool
var questionsData: [QA]
init (volumeNumber: Int, completed: Bool, questionsData: [QA]) {
self.volumeNumber = volumeNumber
self.completed = completed
self.questionsData = questionsData
}
// MARK: NSCoding
public convenience required init?(coder aDecoder: NSCoder) {
let volumeNumber = aDecoder.decodeObject(forKey: "volumeNumber") as! Int
let completed = aDecoder.decodeObject(forKey: "completed") as! Bool
let questionsData = aDecoder.decodeObject(forKey: "questionsData") as! [QA]
self.init(volumeNumber: volumeNumber, completed: completed, questionsData: questionsData)
}
func encode(with aCoder: NSCoder) {
aCoder.encode(volumeNumber, forKey: "volumeNumber")
aCoder.encode(completed, forKey: "completed")
aCoder.encode(questionsData, forKey: "questionsData")
}
}
而我的QA課程i s:
import Foundation
class QA: NSObject {
let questionsText: String
let answerText: [String]
let correctAnswer: [Bool]
var selectedAnswer: [Bool?]
// Create standard initiator
init(questionsText:String, answerText: [String], correctAnswer: [Bool], selectedAnswer: [Bool?]) {
self.questionsText = questionsText
self.answerText = answerText
self.correctAnswer = correctAnswer
self.selectedAnswer = selectedAnswer
}
}
有什麼想法?
'QA'還必須採用'NSCoding' – vadian