CGLayoutKit is a framework with the mission of filling the gaps in Core Graphics layout logic when working with configuring and laying out UIView components. The framework features a collections of extensions for popular UIKit and Core Graphics components in order to make working with them much more streamlined and efficient.

While Auto Layout is officially recommended as the best way to lay out UI components in UIKit, it does have some downsides. When the rules and complexity of the layout become too high, performance can often take a hit. Likewise, when constraints break, debugging what went wrong can sometimes take a long time.

For this reason, sometimes manual frame layout is still the preferred method. However most of the time, it involves a lot of repetitive, hard-to-read math expressions. The goal of CGLayoutKit is to help automate away a lot of the repetitive aspects of these expressions, making manual layout easier to type, and easier to read, without introducing the same performance overhead of Auto Layout.

• Adds semantically named accessors (eg. topLeft) to CGRect and UIView.
• Adds convenient offsetting APIs to CGPoint.
• Adds additional sizing mechanisms to CGSize.
• Streamlines configuring rounded UIView layers and laying out elements in it appropriately.

As a very simple use-case, consider how you would lay out this red view inside of its white container view.

It would probably look something like this.

redView.frame.origin.x = containerView.frame.width - (redView.frame.width + 10)
redView.frame.origin.y = (containerView.frame.height - redView.frame.height) * 0.5

This is super performant and is simple enough to write, but it isn't very easy to read after the fact.

With CGLayoutKit, the equivalent code becomes this.

redView.rightCenter = containerView.bounds.rightCenter.offsetBy(dx: -10)

By defining and using relative anchors, we can achieve a similar flexibility to Auto Layout, but in a much simpler way.

• Swift 5
• UIKit-compatible platforms (iOS, tvOS, Mac Catalyst)

CGLayoutKit is a very simple framework and can be easily imported manually or with CocoaPods.

Drag the CGLayoutKit folder into your Xcode project.

pod 'CGLayoutKit'

I'll add this eventually. But if you want it now, please file a PR!

CGLayoutKit was built as a component of iComics 2 by Tim Oliver

CGLayoutKit is available under the MIT License. Please check the LICENSE file for more information.