Assign xib to the UIView in Swift

This worked for me.

override func awakeAfterUsingCoder(aDecoder: NSCoder) -> AnyObject? {
    if self.subviews.count == 0 {
        return loadNib()
    }
    return self
}

private func loadNib() -> YourCustomView {
    return NSBundle.mainBundle().loadNibNamed("YourCustomViewNibName", owner: nil, options: nil)[0] as YourCustomView
}

for Swift 4

extension UIView {
    class func loadFromNibNamed(nibNamed: String, bundle: Bundle? = nil) -> UIView? {
      return UINib(
          nibName: nibNamed,
          bundle: bundle
      ).instantiate(withOwner: nil, options: nil)[0] as? UIView
  }
}

for Swift 3

You could create an extension on UIView:

extension UIView {
    class func loadFromNibNamed(nibNamed: String, bundle: NSBundle? = nil) -> UIView? {
        return UINib(
            nibName: nibNamed,
            bundle: bundle
        ).instantiateWithOwner(nil, options: nil)[0] as? UIView
    }
}

Note: Using UINib is faster because it does caching for you.

Then you can just do:

ViewDetailItem.loadFromNibNamed("ViewBtnWishList")

And you will be able to reuse that method on any view.