Layoutable is an extension for UIView apps that make use of Auto Layout easier. This framework doesn't replace any existing Auto Layout API available in UIKit. Anchor API is very good and easy to use, but sometimes require a lot of code repetition for common tasks. This framework only adds a couple of useful extensions. You can check the implementation in just one single file.
Usage & features
Here's how the code would look like when constraining the screen above. See the example for the full version.
Just UIKit
import UIKit
final class ViewController: UIViewController {
private let headerView: UIView = {
let view = UIView()
view.backgroundColor = .white
view.translatesAutoresizingMaskIntoConstraints = false
return view
}()
[...]
override func loadView() {
[...]
NSLayoutConstraint.activate([
headerView.topAnchor.constraint(equalTo: view.topAnchor),
headerView.leftAnchor.constraint(equalTo: view.leftAnchor),
headerView.rightAnchor.constraint(equalTo: view.rightAnchor),
headerView.heightAnchor.constraint(equalToConstant: 200),
headerCenterView.widthAnchor.constraint(equalToConstant: 80),
headerCenterView.heightAnchor.constraint(equalToConstant: 80),
headerCenterView.centerXAnchor.constraint(equalTo: headerView.centerXAnchor),
headerCenterView.centerYAnchor.constraint(equalTo: headerView.centerYAnchor),
contentContainerView.topAnchor.constraint(equalTo: headerView.bottomAnchor),
contentContainerView.leftAnchor.constraint(equalTo: view.leftAnchor),
contentContainerView.rightAnchor.constraint(equalTo: view.rightAnchor),
contentContainerView.bottomAnchor.constraint(equalTo: view.bottomAnchor),
contentView.topAnchor.constraint(equalTo: contentContainerView.topAnchor, constant: 80),
contentView.leftAnchor.constraint(equalTo: contentContainerView.leftAnchor, constant: 20),
contentView.rightAnchor.constraint(equalTo: contentContainerView.rightAnchor, constant: -20),
contentView.bottomAnchor.constraint(equalTo: contentContainerView.bottomAnchor, constant: -20),
])
}
}
UIKit + Layoutable
import UIKit
import Layoutable
final class ViewController: UIViewController {
private let headerView: UIView = {
let view = UIView()
view.backgroundColor = .white
return view.layoutable()
}()
[...]
override func loadView() {
[...]
headerView.constrainToSuperviewEdges(excluding: [.bottom])
headerView.heightAnchor.constraint(equalToConstant: 200).isActive = true
headerCenterView.constrainToConstant(size: .init(width: 80, height: 80))
headerCenterView.constrainCenterToSuperview()
contentContainerView.constrainToSuperviewEdges(excluding: [.top])
contentContainerView.topAnchor.constraint(equalTo: headerView.bottomAnchor).isActive = true
contentView.constrainToSuperviewEdges(insets: .init(top: 80, left: 20, bottom: 20, right: 20))
}
}
Detecting if view can be used with Auto Layout
For all of the views that you want to use with Auto Layout you have to type
translatesAutoresizingMaskIntoConstraints = false
.
It's very easy to forget and have a lot of conflicts after running your app.
Layoutable checks for this situation and informs you how to fix it.
Requirements
Layoutable supports iOS 9.0 or higher.
Installation
Carthage
If you're using Carthage, add the following dependency to your Cartfile
:
github "MichalTKwiecien/Layoutable" {version}
CocoaPods
If you're using CocoaPods, add the following dependency to your Podfile
:
pod 'Layoutable', '~> {version}'
Manually
You can just drag and drop single file to your project.
Contributing
Development requires following tools:
After cloning the repository, install project's dependencies:
$ carthage bootstrap --platform iOS