iOS Tutorial => Utilizing Intrinsic Content Size

Example

When creating a UIView subclass, intrinsic content size helps to avoid setting hardcoded height and width constraints

a basic glimpse into how a class can utilize this

class ImageView: UIView {
    var image: UIImage {
        didSet {
            invalidateIntrinsicContentSize()
        }
    }
    // omitting initializers
    // convenience init(image: UIImage)

    override func intrinsicContentSize() -> CGSize {
        return CGSize(width: image.size.width, height: image.size.height)
    }
}

If you only want to provide one size intrinsically, you can provide the value UIViewNoIntrinsicMetric for the value that you wish to ignore.

 override func intrinsicContentSize() -> CGSize {
     return CGSize(width: UIViewNoIntrinsicMetric, height: image.size.width)   
 }

Benefits when using with AutoLayout and Interface Builder

One could take this ImageView (or UIImageView) and set the horizontal alignment to superview center X and the vertical alignment to superview center Y.