This class is not key value coding-compliant for the key…why?

问题

I've linked output from the IB to the code, as shown below.

class DiaryTableViewCell: UITableViewCell {
    @IBOutlet weak var TitleLabel: UILabel!
    @IBOutlet weak var SubTitleLabel: UILabel!
    @IBOutlet weak var leftImageView: UIImageView!
    @IBOutlet weak var rightImageView: UIImageView!
}

Here, I'm registering the class:

override func viewDidLoad() {
   self.title = "My Diary"
   cellNib = UINib(nibName: "TableViewCells", bundle: nil)
   tableView.registerClass(DiaryTableViewCell.classForCoder(), forCellReuseIdentifier: kCellIdentifier)
}

But I keep getting the following runtime error:

*** Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '...setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key SubTitleLabel.'

From within the following code:

override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {

var cell = tableView.dequeueReusableCellWithIdentifier(kCellIdentifier) as DiaryTableViewCell?

if (cell == nil) {
    tableView.registerClass(DiaryTableViewCell.classForCoder(), forCellReuseIdentifier: kCellIdentifier)
    cell = cellNib?.instantiateWithOwner(self, options: nil)[0] as? DiaryTableViewCell
                cell?.selectionStyle = .None
}

if (cell != nil) {
    println("\(x++)) Inside cell")
    cell!.TitleLabel.text = "Hello"
    cell!.SubTitleLabel.text = "World"
}

return cell!
}

Specifically, it's happening here:

cell = cellNib?.instantiateWithOwner(self, options: nil)[0] as? DiaryTableViewCell

Question: How am I violating the key value coding-compliant for a UILabel?

This hasn't happened before... UILabel is KVO compliant.

回答1:

I linked to the WRONG Source!

Here's the result:

回答2:

You should not be calling instantiateWithOwner yourself inside tableView:cellForRowAtIndexPath.

The reason for your particular error is that you are calling instantiateWithOwner passing self as the owner and so the nib is trying to wire the outlets up to your UITableViewDataSource implementation class rather than a DiaryTableViewCell.

回答3:

Show the references of your ViewController rigth-clicking in it on the Document Outline. Probably you will see a warning in one of the references. Delete it and link it again if still need it.

回答4:

sometimes its like when you create button in your xib, you create one button and copy paste other buttons from one buttons, in that case this error occurs, and yes removed connections from xib could also be an reason.

回答5:

I have created a TableViewCell same like your & have the same problem. I have research solving the problem but nothing. Then I delete Label in TableViewCell and recreate again, connect it to TableViewCell through File Owner,v..v And the result is right. No error. You should recreate them again.

来源：https://stackoverflow.com/questions/26729479/this-class-is-not-key-value-coding-compliant-for-the-key-why

标签

ios

uitableview

swift

key-value-observing