swift add width height constraint to view without a lot of code
// Swift3+
let imageView = UIImageView()
imageView.translatesAutoresizingMaskIntoConstraints = false
NSLayoutConstraint.activate([
imageView.widthAnchor.constraint(equalToConstant: 16),
imageView.heightAnchor.constraint(equalToConstant: 16),
])
self.addSubview(self.imageView)