TitledCollectionViewWithProduce.swift

import UIKit

class TitledCollectionView: UIView {

    var produce: Produce? {
        didSet {
            titleLabel.text = produce?.description
        }
    }

    private lazy var vStack: UIStackView = {
        let stack = UIStackView(arrangedSubviews: [titleLabel, collectionView])
        stack.translatesAutoresizingMaskIntoConstraints = false
        stack.axis = .vertical
        stack.distribution = .fill
        stack.alignment = .fill
        stack.spacing = 10
        return stack
    }()

    private lazy var titleLabel: UILabel = {
        let label = UILabel()
        label.translatesAutoresizingMaskIntoConstraints = false
        label.font = .preferredFont(forTextStyle: .title1)
        label.numberOfLines = 1
        return label
    }()

    private lazy var collectionView: UICollectionView = {
        let collectionView = UICollectionView(frame: .zero)
        collectionView.translatesAutoresizingMaskIntoConstraints = false
        return collectionView
    }()

    /// programmatic init
    init(produce: Produce) {
        super.init(frame: .zero)
        // didSet not available in init
        defer { self.produce = produce }
        self.translatesAutoresizingMaskIntoConstraints = false
        // allow gestures to propagate through views
        isUserInteractionEnabled = true
        setupViews()
    }

    required init?(coder: NSCoder) {
        super.init(coder: coder)
        setupViews()
    }

    private func setupViews() {
        backgroundColor = .systemBackground
        addSubview(vStack)

        NSLayoutConstraint.activate([
            vStack.topAnchor.constraint(equalTo: safeAreaLayoutGuide.topAnchor),
            vStack.leadingAnchor.constraint(equalTo: safeAreaLayoutGuide.leadingAnchor),
            vStack.trailingAnchor.constraint(equalTo: safeAreaLayoutGuide.trailingAnchor),
            vStack.bottomAnchor.constraint(equalTo: safeAreaLayoutGuide.bottomAnchor)
        ])
    }

}