Disable horizontal scroll in UIScrollView with autolayout

Question

I want to create view with only vertical scroll. As it turned out it is epic hard to do in iOs. I have done this steps:

1) Create UIViewController in storyboard;

Answer 1

You can also easily do this in code. In my case, I have a UIStackView that's the only subview of a UIScrollView

// Create the stack view
let stackView = UIStackView()
stackView.translatesAutoresizingMaskIntoConstraints = false
// Add things to the stack view....

// Add it as a subview to the scroll view
scrollView.addSubview(stackView)

// Use auto layout to pin the stack view's sides to the scroll view
NSLayoutConstraint.activate([
    stackView.leadingAnchor.constraint(equalTo: scrollView.leadingAnchor),
    scrollView.trailingAnchor.constraint(equalTo: stackView.trailingAnchor),

    stackView.topAnchor.constraint(equalTo: scrollView.topAnchor),
    scrollView.bottomAnchor.constraint(equalTo: stackView.bottomAnchor)
])

// Now make sure the thing doesn't scroll horizontally
let margin: CGFloat = 40

scrollView.contentInset = UIEdgeInsets(top: margin, left: margin, bottom: margin, right: margin)

scrollView.widthAnchor.constraint(equalTo: view.widthAnchor).isActive = true

let stackViewWidthConstraint = stackView.widthAnchor.constraint(equalTo: scrollView.widthAnchor)
stackViewWidthConstraint.constant = -(margin * 2)
stackViewWidthConstraint.isActive = true

The NSLayoutConstraint.activate bit is taken from Dave DeLong's excellent UIView extension here: https://github.com/davedelong/MVCTodo/blob/master/MVCTodo/Extensions/UIView.swift#L26