SwiftUI influences in UIKit

UIStackViews.swift

import UIKit

class VStack: UIStackView {

	init(alignment: UIStackView.Alignment = .fill, spacing: CGFloat = 10, _ arrangedViews: UIView...) {
		super.init(frame: .zero)

		axis = .vertical
		self.alignment = alignment
		self.spacing = spacing
		distribution = .fill

		arrangedViews.forEach(addArrangedSubview)
	}

	required init(coder: NSCoder) {
		fatalError("init(coder:) has not been implemented")
	}

}

class HStack: UIStackView {

	init(alignment: UIStackView.Alignment = .fill, spacing: CGFloat = 10, _ arrangedViews: UIView...) {
		super.init(frame: .zero)

		axis = .horizontal
		self.alignment = alignment
		self.spacing = spacing
		distribution = .fill

		arrangedViews.forEach(addArrangedSubview)
	}

	required init(coder: NSCoder) {
		fatalError("init(coder:) has not been implemented")
	}

}

final class Spacer: UIView {

	init() {
		super.init(frame: .zero)

		autoresizingMask = [.flexibleWidth, .flexibleHeight]

		// These might not be needed, but in case spacers don't work as expected, give them a try.
		// The idea is that a `Spacer` has the lowest priority in hugging, since it doesn't care if it doesn't hug its content (it has none).
		// A `Spacer` also should stop being compressed when other views would stop hugging.

//		setContentHuggingPriority(.init(rawValue: 1), for: .vertical)
//		setContentHuggingPriority(.init(rawValue: 1), for: .horizontal)
//
//		setContentCompressionResistancePriority(.init(rawValue: UILayoutPriority.defaultLow.rawValue - 1), for: .vertical)
//		setContentCompressionResistancePriority(.init(rawValue: UILayoutPriority.defaultLow.rawValue - 1), for: .horizontal)
	}

	required init?(coder: NSCoder) {
		fatalError("init(coder:) has not been implemented")
	}

}

zExample.swift

final class ViewController: UIViewController {

	override func viewDidLoad() {
		super.viewDidLoad()

		view.backgroundColor = .secondarySystemFill

		let image = UIImageView(image: UIImage(named: "pic"))
		image.contentMode = .scaleAspectFill
		image.clipsToBounds = true
		image.translatesAutoresizingMaskIntoConstraints = false

		let nameLabel = UILabel()
		nameLabel.font = UIFont.preferredFont(forTextStyle: .title1)
		nameLabel.text = "Yosemite"

		let infoLabel = UILabel()
		infoLabel.font = UIFont.italicSystemFont(
			ofSize: UIFont.preferredFont(forTextStyle: .caption1).pointSize)
		infoLabel.text = "First climbed in: 1907"

		let detailsStack = VStack(
			spacing: 4,
			detailsRow(labelText: "Difficulty:", valueText: "Hard"),
			detailsRow(labelText: "Annual attempts:", valueText: "1452"),
			detailsRow(labelText: "Monthly successful attempts:", valueText: "12")
		)
		detailsStack.translatesAutoresizingMaskIntoConstraints = false

		let v = UIView()
		v.translatesAutoresizingMaskIntoConstraints = false
		v.backgroundColor = .blue

		let content = VStack(
			spacing: 16,
			image,
			HStack(
				alignment: .lastBaseline,
				nameLabel,
				Spacer(),
				infoLabel
			),
			HStack(
				detailsStack,
				VStack(
					Spacer(),
					HStack(
						v,
						Spacer()
					)
				)
			),
			HStack(
				viewRow(number: 97, icon: "paperplane", text1: "Bird", text2: "species"),
				Spacer(),
				viewRow(number: 20, icon: "eyes", text1: "Breathtaking", text2: "views"),
				Spacer(),
				viewRow(number: 12, icon: "arrow.up", text1: "Oak", text2: "species")
			),
			Spacer()
		)

		content.translatesAutoresizingMaskIntoConstraints = false
		view.addSubview(content)

		NSLayoutConstraint.activate([
			content.topAnchor.constraint(equalTo: view.topAnchor),
			content.bottomAnchor.constraint(equalTo: view.bottomAnchor),
			content.leadingAnchor.constraint(equalTo: view.leadingAnchor, constant: 16),
			content.trailingAnchor.constraint(equalTo: view.trailingAnchor, constant: -16),

			image.heightAnchor.constraint(equalToConstant: 100),
			detailsStack.widthAnchor.constraint(equalToConstant: 250),

			v.heightAnchor.constraint(equalToConstant: 20),
			v.widthAnchor.constraint(equalToConstant: 100),
		])
	}

	private func detailsRow(labelText: String, valueText: String) -> UIView {
		let label = UILabel()
		label.font = UIFont.preferredFont(forTextStyle: .caption1)
		label.text = labelText

		let value = UILabel()
		value.font = label.font
		value.text = valueText

		return HStack(
			label,
			Spacer(),
			value
		)
	}

	private func viewRow(number: Int, icon: String, text1: String, text2: String) -> UIView {
		let numberLabel = UILabel()
		numberLabel.font = UIFont.boldSystemFont(ofSize: UIFont.preferredFont(forTextStyle: .title1).pointSize)
		numberLabel.text = "\(number)"

		let text1Label = UILabel()
		text1Label.font = UIFont.preferredFont(forTextStyle: .caption1)
		text1Label.text = text1

		let text2Label = UILabel()
		text2Label.font = text1Label.font
		text2Label.text = text2

		let image = UIImage(systemName: icon,
							withConfiguration: UIImage.SymbolConfiguration(font: text1Label.font))?
			.withRenderingMode(.alwaysOriginal)
		let imageView = UIImageView(image: image)
		imageView.contentMode = .scaleAspectFit

		return HStack(
			alignment: .lastBaseline,
			numberLabel,
			VStack(
				spacing: 0,
				HStack(
					spacing: 2,
					imageView,
					text1Label,
					Spacer()
				),
				text2Label
			)
		)
	}

}

This is the example's output: