Tablecloth

A tiny little Auto Layout "DSL" library based on Auto Layout with Key Paths by Swift Talk.

Usage

Tablecloth wraps the creation of NSLayoutConstraints in a custom Constraint type.

The following snippet adds a view imageView to view and pins it to view's leading layout margin anchor, makes them the same height and centers the imageView vertically.

view.addSubview(imageView) {
  equal(\.leadingAnchor, \.layoutMarginsGuide.leadingAnchor)
  equal(\.heightAnchor)
  equal(\.centerYAnchor)
}

Or you can add a view and make it fill its superview.

view.addSubview(scrollView, constraints: .toFrame)

You can also constrain a view to other view's in the view hierarchy.

view.addSubview(label) {
  equal(\.leadingAnchor, \.trailingAnchor, of: firstLabel).constant(16)
}

The modifiers .constant() and .multiplier() and .priority() can be used to modify a constraint's properties.

If you need to do something with an actual NSLayoutConstraint after it's been created, like storing a reference to it, you can use the .with() modifier.

titleLabel.configureConstraints {
  equal(\.widthAnchor, of: stackView).constant(-16).with { widthConstraint = $0 }
}

Documentation

All of the code is fairly well documented, albeit probably riddled with copy-paste errors. Checkout Tablecloth.swift and View.swift for the most relevant bits.

On Production Readyness

This code has been used with great success in Plantry for years. It does however not contain everything required to build any layout imaginable.

License

MIT