how to set background colour of a container view - swift

Question

i have dragged a container view from storyboard and set it black in background colour. but it didn't change the background colour.
class ViewController: UIViewController {
#IBOutlet weak var container: UIView!
override func viewDidLoad() {
super.viewDidLoad()
container.layer.backgroundColor = UIColor.blackColor().CGColor
// Do any additional setup after loading the view, typically from a nib.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}

Answer 1

How did you set the background color?
A container view is actually just a normal view, that is linked to a viewController. This means you can set the background the same way as you would for any other NSView or UIView. This is all the code I needed to add to my NSViewController class (not the ViewController inside the container, just the ViewController for the window).
#IBOutlet weak var containerView: NSView!
override func viewDidLoad() {
//other code in your viewDidLoad
containerView.wantsLayer = true
}
override func awakeFromNib() {
super.awakeFromNib()
containerView.layer?.backgroundColor = NSColor.black.cgColor
}
make sure to connect the IBOutlet if you have not already.
If you set the layers background color in viewDidLoad, the layer may not exist yet, (I don't know why). Accessing the layer in awakeFromNib has always worked for me, while accessing it in the viewDidLoad can be unreliable.
If you are working on IOS, most of this is not applicable, and this should be all you need
#IBOutlet weak var containerView: UIView!
override func viewDidLoad() {
containerView.layer?.backgroundColor = UIColor.black.cgColor
}
I work less on IOS, so I have not ran into any issues with that, but that could be from lack of attempts. On OSX setting the background color in viewDidLoad will work about 50% of the time so there might still be an issue that I have not ran into.
If neither works, try unwrapping the layer rather than leaving it an optional (replacing the ? with a !) this will at least crash your program and probably tell you that layer is nil, if this is the case you should be figuring out why the layer is nil.
Also if the ViewController connected to the container view is a custom class, you don't have to bother with the IBOutlets, just call the view "view" in that custom class.
Sorry this got a bit long, but hope this helped