Question

我在Xcode中创建一个应用程序，我需要在UITableViewController中添加一个名为PeopleTableViewController的人，导航栏中的Add Button用于连接到NewPersonViewController，即UIViewController。

但是当我点击“+”按钮时，它会显示

线程1：发出SIGABRT信号错误。

 Terminating app due to uncaught exception 'NSUnknownKeyException',
 reason: '[<Draft3.NewPersonViewController 0x7f9148636650>
 setValue:forUndefinedKey:]: this class is not key value
 coding-compliant for the key savePerson.'

以下是Main.Storyboard

的屏幕截图

以下是NewPersonViewController的代码：

import UIKit

class NewPersonViewController: UIViewController {

@IBOutlet weak var personNameTextField: UITextField!

    override func viewDidLoad() {
        super.viewDidLoad()

        personNameTextField.delegate = self as? UITextFieldDelegate


    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {

        personNameTextField.resignFirstResponder()

    }


    @IBAction func savePerson(_ sender: UIBarButtonItem) {
        let person = People(title: personNameTextField.text ?? "")

        do {
            try person?.managedObjectContext?.save()

            self.navigationController?.popViewController(animated: true)
        } catch {
            print("Could not save the person's name")
        }
    }
}

extension NewPersonViewController: UITextFieldDelegate {
    func textFieldShouldReturn(_ textField: UITextField) -> Bool {
        textField.resignFirstResponder()
        return true
    }
}

以下是PeopleTableViewController的代码：

import UIKit
import CoreData

class PeopleTableViewController: UITableViewController {

    @IBOutlet weak var peopleTableView: UITableView!

    var people: [People] = []

    override func viewDidLoad() {
        super.viewDidLoad()

        // Uncomment the following line to preserve selection between presentations
        // self.clearsSelectionOnViewWillAppear = false

        // Uncomment the following line to display an Edit button in the navigation bar for this view controller.
        // self.navigationItem.rightBarButtonItem = self.editButtonItem
    }

    //ViewWillAppear allows us to fetch all the data in the backend and help us display to the user
    override func viewWillAppear(_ animated: Bool) {
        guard let appDelegate = UIApplication.shared.delegate as? AppDelegate else {
            return
        }

        let managedContext = appDelegate.persistentContainer.viewContext

        let fetchRequest: NSFetchRequest<People> =  People.fetchRequest()

        do {
            people = try managedContext.fetch(fetchRequest)

            peopleTableView.reloadData()
        } catch {
            print("Could not fetch")
        }
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }


    @IBAction func addButtonPressed(_ sender: UIBarButtonItem) {

        performSegue(withIdentifier: "addPeople", sender: self)

    }

}

Answer 1

您是否检查过@IBAction和@IBOutlet是否已正确绑定到故事板？

'NSUnknownKeyException', reason: '[ setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key savePerson.'感觉@IBAction或IBOutlet未正确绑定，或者您没有为故事板中的视图控制器正确设置类。在我看来，它试图访问方法savePerson，但无法在绑定类中找到它。

如何在Xcode中解决线程1：信号SIGABRT错误？

1 个答案: