ScrollView with StackView and auto layout

ViewController.swift

class ViewController: UIViewController {
    override func loadView() {
        super.loadView()

        let view = UIView()
        view.backgroundColor = .systemBackground

        let scrollView = UIScrollView()
        scrollView.translatesAutoresizingMaskIntoConstraints = false

        let stackView = UIStackView(arrangedSubviews: [])
        for i in 1...100 {
            let label = UILabel()
            label.textColor = .label
            label.text = "\(i)"
            stackView.addArrangedSubview(label)
        }

        stackView.axis = .horizontal
        stackView.distribution = .equalSpacing
        stackView.spacing = 8.0
        stackView.translatesAutoresizingMaskIntoConstraints = false
        scrollView.addSubview(stackView)
        view.addSubview(scrollView)
        NSLayoutConstraint.activate([
            .init(item: view, attribute: .trailing, relatedBy: .equal, toItem: scrollView, attribute: .trailing, multiplier: 1.0, constant: 0.0),
            .init(item: view, attribute: .centerY, relatedBy: .equal, toItem: scrollView, attribute: .centerY, multiplier: 1.0, constant: 0.0),
            .init(item: view, attribute: .leading, relatedBy: .equal, toItem: scrollView, attribute: .leading, multiplier: 1.0, constant: 0.0),
            .init(item: view, attribute: .centerX, relatedBy: .equal, toItem: scrollView, attribute: .centerX, multiplier: 1.0, constant: 0.0),
            .init(item: scrollView, attribute: .height, relatedBy: .equal, toItem: nil, attribute: .notAnAttribute, multiplier: 1.0, constant: 100.0),
            .init(item: scrollView, attribute: .trailing, relatedBy: .equal, toItem: stackView, attribute: .trailing, multiplier: 1.0, constant: 0.0),
            .init(item: scrollView, attribute: .leading, relatedBy: .equal, toItem: stackView, attribute: .leading, multiplier: 1.0, constant: 0.0),
            .init(item: scrollView, attribute: .top, relatedBy: .equal, toItem: stackView, attribute: .top, multiplier: 1.0, constant: 0.0),
            .init(item: scrollView, attribute: .bottom, relatedBy: .equal, toItem: stackView, attribute: .bottom, multiplier: 1.0, constant: 0.0),
            .init(item: scrollView, attribute: .height, relatedBy: .equal, toItem: stackView, attribute: .height, multiplier: 1.0, constant: 0.0),
        ])
        self.view = view
    }
    init() {
        super.init(nibName: nil, bundle: nil)
    }

    required init?(coder: NSCoder) {
        fatalError()
    }
}