尝试使用元组保存时出现核心数据错误

Question

当我尝试将字符串保存到我的新工作笔记类中的 coreData 时，我收到此错误。它似乎在行let tuple = CoreDataManager.shared.createJobNote(jobNote: jobNote, job: job)上的函数private func createNote()崩溃

这是错误：

2018-05-03 17：37：53.180012+0100 拍摄[7022：3228759] *** 由于未捕获的异常"NSInvalidArgumentException"而终止应用程序，原因："属性的不可接受的值类型：属性 = "注释";所需类型 = NSString;给定类型 = JobNote;值 = (实体：JobNote;id：0x1c002f080;数据：{ 作业 ="0xd000000000580000"; 注意 = 无; }).'

我有一个名为Job的实体，用于存储作业名称 - 然后我将其传递给我的 JobNoteVC。

我还有一个名为：JobNote的实体，其属性名为：note。我还为我的核心数据制作了一个结构：

func createJobNote(jobNote: String, job: Job) -> (JobNote?, Error?) {
let context = persistentContainer.viewContext
// create note
let jobNote = NSEntityDescription.insertNewObject(forEntityName: "JobNote", into: context) as! JobNote
jobNote.job = job
jobNote.setValue(jobNote, forKey: "note")
do {
try context.save()
return (jobNote, nil)
} catch let error {
print ("Failed to add camera:", error)
return (nil, error)
}
}

然后，我有一个笔记页面，其中包含一个表视图，该视图将显示存储在coredata中的所有笔记：

import UIKit
import CoreData
class notes : UIViewController, UITableViewDelegate, UITableViewDataSource, NewJobNoteControllerDelegate {
let cellId = "cellId"
var tableView = UITableView()
var jobNotesArray = [JobNote]()
var job: Job? {
let tabBarController = self.tabBarController as! jobTabController
return tabBarController.job
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
self.tabBarController?.navigationItem.title = "NOTES"
let addButton = UIBarButtonItem(barButtonSystemItem: .add, target: self, action: #selector(HandleNewNote))
self.tabBarController?.navigationItem.rightBarButtonItems = [addButton]
addTableView()
fetchJobNotes()
}
func addTableView() {
// TABLE VIEW SETUP
tableView.frame = self.view.frame
self.view.addSubview(tableView)
tableView.delegate = self
tableView.dataSource = self
}
private func fetchJobNotes(){
guard let jobNotes = job?.jobNotes?.allObjects as? [JobNote] else { return }
self.jobNotesArray = jobNotes
}
func didAddJobNote(jobNote: JobNote) {
jobNotesArray.append(jobNote)
tableView.reloadData()
}
func didEditJobNote(jobNote: JobNote) {
let row = jobNotesArray.index(of: jobNote)
let reloadIndexPath = IndexPath(row: row!, section: 0)
tableView.reloadRows(at: [reloadIndexPath], with: .middle)
}
@IBAction func HandleNewNote(sender : UIButton) {
let newNote = newJobNote()
newNote.delegate = self
newNote.job = job
let navController = UINavigationController(rootViewController: newNote)
present(navController, animated: true, completion: nil)
}
func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return jobNotesArray.count
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = UITableViewCell(style: .default, reuseIdentifier: nil)
return cell
}
}

这是我的新笔记VC：

import CoreData
protocol NewJobNoteControllerDelegate {
func didAddJobNote(jobNote : JobNote)
func didEditJobNote(jobNote: JobNote)
}
class newJobNote: UIViewController {
var delegate: NewJobNoteControllerDelegate?
var job: Job?
let noteLabel: UILabel = {
let label = UILabel()
label.text = "NOTE"
label.translatesAutoresizingMaskIntoConstraints = false
label.textColor = UIColor(red:0.63, green:0.63, blue:0.63, alpha:1.0)
return label
}()
var noteTextField: UITextField = {
let textField = UITextField()
textField.placeholder = "Enter Note..."
textField.tintColor = UIColor(red:0.87, green:0.30, blue:0.32, alpha:1.0)
textField.translatesAutoresizingMaskIntoConstraints = false
return textField
}()

var jobNote : JobNote? {
didSet {
noteTextField.text = jobNote?.note
}
}
override func viewDidLoad() {
super.viewDidLoad()
view.backgroundColor = UIColor.white
let backButton = UIBarButtonItem(barButtonSystemItem: .save, target: self, action: #selector(HandleBack))
navigationItem.leftBarButtonItem = backButton
}
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
navigationItem.title = "NEW NOTE"
}
private func createNote() {
guard let jobNote = noteTextField.text else { return }
guard let job = self.job else { return }
let tuple = CoreDataManager.shared.createJobNote(jobNote: jobNote, job: job)
if let error = tuple.1 {
print(error)
} else {
dismiss(animated: true, completion: {
self.delegate?.didAddJobNote(jobNote: tuple.0!)
})
}
}
private func saveNoteChanges() {
let context = CoreDataManager.shared.persistentContainer.viewContext
jobNote?.note = noteTextField.text
do {
try context.save()
dismiss(animated: true) {
self.delegate?.didEditJobNote(jobNote: self.jobNote!)
}
} catch let error {
print ("Failed to save camera changes:", error)
}
}
@IBAction private func HandleBack(sender : UIButton) {
if jobNote == nil {
createNote()
print("back to note and saved")
} else {
saveNoteChanges()
print("back to note and saved")
}
}
}

Answer 1

问题就在这里

jobNote.setValue(jobNote, forKey: "note")

不能将实体实例设置为实体本身内部的属性，更改参数名称

func createJobNote(sendedNote: String, job: Job) -> (JobNote?, Error?) {
let context = persistentContainer.viewContext
// create note
let jobNote = NSEntityDescription.insertNewObject(forEntityName: "JobNote", into: context) as! JobNote
jobNote.job = job
jobNote.setValue(sendedNote, forKey: "note")
do {
try context.save()
return (jobNote, nil)
} catch let error {
print ("Failed to add camera:", error)
return (nil, error)
}
}