Question

选择表格单元格后，我希望它在segue之后在我的详细信息视图中填充文本字段。

这是我在此网站上找到的一种方法（我尝试了其他在这里看到的方法，但是在将代码转换为与核心数据和/或自定义单元格结合使用时出现错误/问题），但不会返回错误，填写字段


    func tableView(_ tableView: UITableView,
                   cellForRowAt indexPath: IndexPath) -> UITableViewCell
    {
        //(print(tableView.dequeueReusableCell(withIdentifier: "PartyCell", for: indexPath)))

        //  get selected row (party)
        let party = parties[indexPath.row] as NSManagedObject

        //  create custom cell
        let cell = tableView.dequeueReusableCell(withIdentifier: "PartyCell",
                                                 for: indexPath) as! PartyCell

        //  Update the custom cell labels with information from record
        cell.nameLabel?.text = party.value(forKeyPath: "name") as? String
        cell.sizeLabel.text = party.value(forKeyPath: "size") as? String
        cell.contactLabel.text = party.value(forKeyPath: "contact") as? String
        cell.locationLabel.text = party.value(forKeyPath: "location") as? String

        return cell
    }

    func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath)
    {


        // Create a variable that you want to send based on the destination view controller
        // Get a reference to the data by using indexPath shown below
        let party = parties[indexPath.row]

        // Create an instance of DestinationViewController and pass the variable
        let destinationVC = DetailViewController()


        destinationVC.nameField.text = party.value(forKeyPath: "name") as? String
        destinationVC.sizeField.text = party.value(forKeyPath: "size") as? String
        destinationVC.contactField.text = party.value(forKeyPath: "contact") as? String
        destinationVC.locationField.text = party.value(forKeyPath: "name") as? String


        // Let's assume that the segue name is called playerSegue
        // This will perform the segue and pre-load the variable for you to use
        destinationVC.performSegue(withIdentifier: "mySegue", sender: self)

    }

这是已建立插座连接的详细视图

import Foundation
import UIKit
import CoreData

class DetailViewController: UIViewController
{

    //let party = NSEntityDescription.insertNewObjectForEntityForName("Party", inManagedObjectContext: managedObjectContext) as! Party


    @IBOutlet weak var nameField: UITextField!
    @IBOutlet weak var sizeField: UITextField!
    @IBOutlet weak var contactField: UITextField!
    @IBOutlet weak var locationField: UITextField!

    override func viewWillAppear(_ animated: Bool)
    {

    }

}

Answer 1

您可以在您的detailviewcontroller中添加一个变量：

class DetailViewController: UIViewController { 
    var party: Party!
}

使用segue传递所选方；所以在didSelectRowAt

let destinationVC = UIStoryboard(name: "yourStory", bundle: nil).instantiateViewController(withIdentifier: "yourId") as! DetailViewController()
destinationVC.party = selectedParty
destinationVC.performSegue(withIdentifier: "mySegue", sender: self)

然后在您的viewDidLoad中的DetailViewController中设置营业网点：

override func viewDidLoad() {
   super.viewDidLoad()
   nameField.text = party.something
//and so on!
}

Answer 2

三个致命错误：

DetailViewController()不是情节提要中的实例。
即使在初始化控制器后，插座仍未连接。
您必须在主视图控制器上而不是在DetailViewController上执行segue。

解决方案：

在didSelectRowAt中调用self.performSegue并将受管理对象作为sender

传递

func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath)
{
    performSegue(withIdentifier: "mySegue", sender: parties[indexPath.row])
}

在DetailViewController中声明一个NSManagedObject属性。

class DetailViewController: UIViewController
{

    var party : NSManagedObject!

    ...

执行prepare(for segue并将NSManagedObject对象分配给临时属性。

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    guard segue.identifier == "mySegue" else { return }
    let detailViewController = segue.destination as! DetailViewController
    detailViewController.party = sender as! NSManagedObject
}

在viewDidLoad的{{1}}中，将属性分配给出口。
```
DetailViewController
```

所选表格单元格信息未使用核心数据显示在详细视图中，没有错误

2 个答案: