How is it fashionable to make Constraints in code these days?

Question

iOS

Actually, what is better to use now?
NSLayoutConstraint :

NSLayoutConstraint(item: stackView,
  attribute: .leading,
  relatedBy: .equal,
  toItem: view,
  attribute: .leadingMargin,
  multiplier: 1,
  constant: 0).isActive = true

Visual Format Language :

let v = NSLayoutConstraint.constraints(
  withVisualFormat: "V:|[topLayoutGuide]-[stackView]",
  options: [],
  metrics: nil,
  views: views)
NSLayoutConstraint.activate(v)

Layout Anchors :

myView.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
myView.bottomAnchor.constraint(equalTo: view.topAnchor,
       constant: 8).isActive=true

Do they use StackViews? And what about Traits in the code?

Answer 1

LayoutAnchor came with iOS 9, so if you have support with iOS 9, then use it, it's easy to write and more readable.
NSLayoutConstraint vs Visual Format Language
I preferred the first, the second was less clear to me, and it's easier to make a mistake there.
StackView is used, but without fanaticism, especially in table cells.
What's wrong with Traits? If you have support for multiple orientations, then use.