Some very useful UIView extension ideas.

UIViewExtension.swift

import UIKit

extension UIView {
    func addConstraintToLayoutSubviewInCenter(_ subview: UIView, size: CGSize? = nil) {
        subview.translatesAutoresizingMaskIntoConstraints = false
        subview.centerXAnchor.constraint(equalTo: centerXAnchor, constant: 0).isActive = true
        subview.centerYAnchor.constraint(equalTo: centerYAnchor, constant: 0).isActive = true
        if let _size = size {
            subview.widthAnchor.constraint(equalToConstant: _size.width).isActive = true
            subview.heightAnchor.constraint(equalToConstant: _size.height).isActive = true
        }
    }
    func circular() {
        layer.cornerRadius = frame.size.height / 2
        clipsToBounds = true
    }
    func applyShadow(color: UIColor = .black, offset: CGSize = CGSize(width: 0.0, height: 1.0), opacity: Float = 0.2, radius: Float = 1.0) {
        layer.shadowColor = color.cgColor
        layer.shadowOffset = offset
        layer.shadowOpacity = opacity
        layer.shadowRadius = CGFloat(radius)
        layer.masksToBounds = false
    }
    func applyGlow(color: UIColor) {
        layer.shadowColor = color.cgColor
        layer.shadowOffset = .zero
        layer.shadowOpacity = 0.5
        layer.shadowRadius = 10
        layer.masksToBounds = false
    }
}