VStackViewController.swift

import UIKit

open class VStackViewController: UIViewController {
    public let scrollView: UIScrollView = .init()
    public let stackView: UIStackView = {
        let stackView: UIStackView = .init()
        stackView.axis = .vertical
        stackView.alignment = .fill
        stackView.distribution = .equalSpacing
        stackView.spacing = 0
        return stackView
    }()

    var components: [UIViewController]

    public init(components: [UIViewController]) {
        self.components = components
        super.init(nibName: nil, bundle: nil)
    }

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

    override open func viewDidLoad() {
        super.viewDidLoad()

        components.forEach { [weak self] in self?.addChild($0) }

        view.addSubview(scrollView, constraints: .allEdges())
        scrollView.addSubview(stackView, constraints: .allEdges() + [equal(\.widthAnchor)])

        components.forEach { [weak self] in
            guard let self = self else { return }
            self.stackView.addArrangedSubview($0.view)
        }
        components.forEach { [weak self] in
            guard let self = self else { return }
            $0.didMove(toParent: self)
        }
    }
}