wvabrinskas / Paver

Ultra lightweight UIView layout utility

Support

Introduction

Paver is a super lightweight UIView layout utility. It's effectively an extension on UIView allowing for quick constraint assignment to any view. It reduces the complexity of using the built-in AutoLayout by wrapping a lot of the verbose assignments to easy to read functions and variables.

Usage

Create a UIView conforming view and add it to some parent view you want to have AutoLayout apply to.

let button = UIButton(frame: .zero)
let button2 = UIButton(frame: .zero)

view.addSubview(button)
view.addSubview(button2)

Once the views are created you can simply call apply() on the new views to set the constraints:

button.apply { paver in [
    paver.size.height.constant(50),
    paver.size.width.constant(100),
    paver.center.x.to(view),
    paver.center.y.to(view)
]}

button2.apply { paver in [
    paver.size.height.constant(50),
    paver.size.width.constant(100),
    paver.center.x.to(view),
    paver.aligment.top.to(button, constant: 50)
]}

apply is a function extension on UIView func apply(_ constraints: (_ paver: Paver) -> [NSLayoutConstraint?]) { that takes in a block that expects an array of NSLayoutConstraint as a return value.

Calling apply will automatically take care of the layout for you. That's it!

UIView Convienence Functions

setSizeEqual(to view: UIView)

• Sets the caller's size equal to the passed in view

setSizeEqual(to size: CGSize)

• Set the caller's size equal to the passing size.

center(in view: UIView, size: CGSize)

• Set the caller's position to the center of the passed in view while also setting the size of the caller.

Constraints functions

Functions that are useful in the apply block.

to(_ view: UIView, constant: CGFloat = 0) -> NSLayoutConstraint

• Sets a UIView.AnchorProduct equal to the passed in views equivalent AnchorPoint with a constant adjustment.

lessThanOrEqualTo(_ view: UIView, constant: CGFloat = 0) -> NSLayoutConstraint

• Sets a UIView.AnchorProduct lessThanOrEqualTo the passed in views equivalent AnchorPoint with a constant adjustment.

greaterThanOrEqualTo(_ view: UIView, constant: CGFloat = 0) -> NSLayoutConstraint

• Sets a UIView.AnchorProduct greaterThanOrEqualTo the passed in views equivalent AnchorPoint with a constant adjustment.