Subtitled navigation title view

SubtitledNavigationTitleView.swift

class SubtitledNavigationTitleView: UIView {

    let titleLabel: UILabel = {
        let label = UILabel()
        label.adjustsFontForContentSizeCategory = true
        label.font = .preferredFont(forTextStyle: .headline)
        label.textAlignment = .center
        label.numberOfLines = 1
        return label
    }()

    let subtitleLabel: UILabel = {
        let label = UILabel()
        label.adjustsFontForContentSizeCategory = true
        label.font = .preferredFont(forTextStyle: .caption1)
        label.lineBreakMode = .byTruncatingTail
        label.textAlignment = .center
        label.textColor = .secondaryLabel
        label.numberOfLines = 1
        return label
    }()

    override var intrinsicContentSize: CGSize {
        return UIView.layoutFittingCompressedSize
    }

    override init(frame: CGRect) {
        super.init(frame: frame)

        setup()
    }

    @available(*, unavailable)
    required init?(coder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    private func setup() {

        addSubview(titleLabel)
        addSubview(subtitleLabel)

        titleLabel.translatesAutoresizingMaskIntoConstraints = false
        subtitleLabel.translatesAutoresizingMaskIntoConstraints = false

        NSLayoutConstraint.activate([
            titleLabel.topAnchor.constraint(equalTo: topAnchor),
            titleLabel.leadingAnchor.constraint(equalTo: leadingAnchor),
            titleLabel.trailingAnchor.constraint(equalTo: trailingAnchor),
            subtitleLabel.topAnchor.constraint(equalTo: titleLabel.bottomAnchor),
            subtitleLabel.leadingAnchor.constraint(equalTo: titleLabel.leadingAnchor),
            subtitleLabel.trailingAnchor.constraint(equalTo: titleLabel.trailingAnchor),
            subtitleLabel.bottomAnchor.constraint(equalTo: bottomAnchor)
        ])

    }

}