Could you explain the basics of using Auto Layout for arranging elements in an interface?

Auto Layout is a system for automatically positioning and resizing interface elements in iOS. It allows you to set rules (constraints) that describe the relative placement and sizes of elements in relation to each other or their container.

Basics of usage:

• Create constraints that link elements to other elements or to the edges of the superview.
• Use priorities and relations (equal, greaterThanOrEqual, lessThanOrEqual) for flexibility.
• Auto Layout automatically calculates the sizes and positions of elements when the screen size or orientation changes.

Example in Swift:

let button = UIButton()
button.translatesAutoresizingMaskIntoConstraints = false
view.addSubview(button)
NSLayoutConstraint.activate([
    button.centerXAnchor.constraint(equalTo: view.centerXAnchor),
    button.centerYAnchor.constraint(equalTo: view.centerYAnchor),
    button.widthAnchor.constraint(equalToConstant: 100),
    button.heightAnchor.constraint(equalToConstant: 50)
])

In this example, the button is centered on the screen with fixed dimensions.