ios - 此类不符合键的键值编码

Question

我对快速开发非常陌生，我正在研究 this section苹果提供了快速教程。我为嵌套在表格单元格中的标签、图像和自定义 View 创建了一个导出。当我运行时出现此错误

2016-07-20 23:16:11.110 FoodTracker[8446:3016336] Unknown class MealTableViewCell in Interface Builder file. 2016-07-20 23:16:11.124 FoodTracker[8446:3016336] * Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[ setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key nameLabel.' * First throw call stack:

没有重复的导出，我相信我的 TableView Controller 中使用的 cellIdentifier 是正确的。我的表格单元格

import UIKit

class MealTableViewCell: UITableViewCell {

//    MARK: Properties
@IBOutlet weak var nameLabel: UILabel!
@IBOutlet weak var photoImageView: UIImageView!
@IBOutlet weak var ratingControl: RatingControl!

override func awakeFromNib() {
    super.awakeFromNib()
}

override func setSelected(selected: Bool, animated: Bool) {
    super.setSelected(selected, animated: animated)
}}

我的 TableView Controller

import UIKit

class MealTableViewController: UITableViewController {
// MARK: Properties

var meals = [Meal]()

override func viewDidLoad() {
    super.viewDidLoad()
    loadSampleMeals()
}

func loadSampleMeals() {
    let photo1 = UIImage(named: "meal1")!
    let meal1 = Meal(name: "Caprese Salad", photo: photo1, rating: 4)!

    let photo2 = UIImage(named: "meal2")!
    let meal2 = Meal(name: "Chicken and Potatoes", photo: photo2, rating: 5)!

    let photo3 = UIImage(named: "meal3")!
    let meal3 = Meal(name: "Pasta with Meatballs", photo: photo3, rating: 3)!

    meals += [meal1, meal2, meal3]
}

override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
    return 1
}

override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
    return meals.count
}

override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
    // Table view cells are reused and should be dequeued using a cell identifier.
    let cellIdentifier = "MealTableViewCell"
    let cell = tableView.dequeueReusableCellWithIdentifier(cellIdentifier, forIndexPath: indexPath) as! MealTableViewCell

    // Fetches the appropriate meal for the data source layout.
    let meal = meals[indexPath.row]

    cell.nameLabel.text = meal.name
    cell.photoImageView.image = meal.photo
    cell.ratingControl.rating = meal.rating

    return cell
}}

谢谢!

Answer 1

检查 Storyboard文件中是否存在损坏的 socket 链接。找到您的 Controller 和control - 单击其 Nib 上方的黄色圆圈以打开操作和导出弹出窗口。您应该会看到带有黄色警告标志的 nameLabel 导出。将其重新连接到 Controller 的文件，或者将其删除(如果重复)。