UITableViewCell subclass IBOutlets returns nil
I've set up an UITableViewCell subclass from storyboard and connected the subviews as IBOutlets, as you can check here:
public class WaitingStatusTableViewCell: UITableViewCell {
@IBOutlet weak var leftBoxView: UIView!
@IBOutlet weak var leftTimeLabel: UILabel!
@IBOutlet weak var leftTitleLabel: UILabel!
Overrided the initialisers:
override init(style: UITableViewCellStyle, reuseIdentifier: String?) {
super.init(style: style, reuseIdentifier: reuseIdentifier)
self.initialConfigure()
}
required public init(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
self.initialConfigure()
}
And on the initialConfigure function I try to configure some properties of my subviews
func initialConfigure() {
self.leftBoxView.backgroundColor = UIColor.clearColor()
self.leftBoxView.layer.shadowColor = UIColor.darkGrayColor().CGColor
self.leftBoxView.layer.shadowPath = UIBezierPath(roundedRect: bounds, cornerRadius: 12.0).CGPath
self.leftBoxView.layer.shadowOffset = CGSize(width: 2.0, height: 2.0)
self.leftBoxView.layer.shadowOpacity = 1.0
self.leftBoxView.layer.shadowRadius = 2
self.leftBoxView.layer.masksToBounds = true
self.leftBoxView.clipsToBounds = false
}
It doesn't work at all, I receive the following error:
fatal error: unexpectedly found nil while unwrapping an Optional value
Any ideas?
Oh, by the way, it works on drawsRect function, but I really want to understand the "why"
It all comes down to the order of execution:
Here are key moments that occur in sequence when the view is loaded:
init() is called on your table view subclass and an instance of the class is created. At this time all IBOutlets are nil . That's why you're getting this error. awakeFromNib() is then called, at which point your IBOutlets will no longer be have nil value so long as they have been properly linked through a storyboard. drawRect() is called last, when the view is ready to be drawn to the screen So, the solution is to move self.initialConfigure() into the awakeFromNib method:
override func awakeFromNib() {
super.awakeFromNib()
self.initialConfigure()
}
And trust that iOS will work its magic.
Here is an excellent article detailing the sequence of events that occur when a view is created, if you want to know more on the subject.
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