UIStackView - why is the stack positioned one on top of the other? - swift

Question

I am trying to get a group of buttons arranged within a stack view. However, when i use a for-each loop to do this, the buttons end up being positioned one on top of the other?
var stackView: UIStackView = {
let sView = UIStackView()
sView.axis = .vertical
sView.distribution = .fill
sView.alignment = .center
return sView
}()
var optionTitles = ["Sign in", "sign out"]
for title in optionTitles{
let btn = UIButton()
btn.setTitle(title, for: .normal)
btn.backgroundColor = optionColour.withAlphaComponent(0.6)
allButtons.append(btn)
stackView.addSubview(btn)
}
// Auto layout constraints
for button in allButtons{
button.translatesAutoresizingMaskIntoConstraints = false
button.heightAnchor.constraint(equalToConstant: optionHeight).isActive = true
button.widthAnchor.constraint(equalTo: stackView.widthAnchor).isActive = true
}
view.addSubview(stackView)
stackTopConstraint = stackView.topAnchor.constraint(equalTo: view.safeAreaLayoutGuide.topAnchor)
stackBottomConstraint = stackView.bottomAnchor.constraint(equalTo: view.topAnchor)
stackView.translatesAutoresizingMaskIntoConstraints = false
stackView.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
stackTopConstraint!.isActive = true
stackView.widthAnchor.constraint(equalTo: view.widthAnchor).isActive = true

Answer 1

2 things
1- You need to remove this
button.widthAnchor.constraint(equalTo: stackView.widthAnchor).isActive = true
2- Replace
stackView.addSubview(btn)
with
stackView.addArrangedSubview(btn)

Answer 2

You have:
stackTopConstraint = stackView.topAnchor.constraint(equalTo: view.safeAreaLayoutGuide.topAnchor)
stackBottomConstraint = stackView.bottomAnchor.constraint(equalTo: view.topAnchor)
You probably meant view.bottomAnchor in the second line. Surely you don't want to constraint the bottom of the stack view to the top of your view.