MarkerKit

A lightweight and easy to use wrapper for Auto Layout Constraints (iOS 8+ support), inspired by https://github.com/ustwo/autolayout-helper-swift

Requirements

• iOS 8.0+
• Xcode 9.0+
• Swift 4.0+

Installation

CocoaPods

You can use CocoaPods.

platform :ios, '8.0'
use_frameworks!

target 'MyApp' do
  pod 'MarkerKit'
end

Carthage

You can use Carthage. Specify in Cartfile:

github "pchelnikov/MarkerKit"

Run carthage to build the framework and drag the built MarkerKit.framework into your Xcode project. Follow build instructions.

Manually

• Add the MarkerKit.swift file to your Xcode project.

Usage

Quick Start

import MarkerKit

class MyViewController: UIViewController {

    lazy var myView = UIView()

    override func viewDidLoad() {
        super.viewDidLoad()

        view.addSubview(myView)
        
        myView.mrk.height(50)
        myView.mrk.width(50)
        myView.mrk.center(to: view)
    }
}

More examples:

Edges placing

// Create view
    
let myView = UIView()
myView.backgroundColor = UIColor.red
view.addSubview(myView)
    
// Add constraints
    
myView.mrk.top(to: view, attribute: .top, relation: .equal, constant: 10.0)
myView.mrk.leading(to: view, attribute: .leading, relation: .equal, constant: 10.0)
myView.mrk.trailing(to: view, attribute: .trailing, relation: .equal, constant: -10.0)
myView.mrk.bottom(to: view, attribute: .bottom, relation: .equal, constant: -10.0)

or shorter you can omit the attributes:

myView.mrk.top(to: view, constant: 10.0)
myView.mrk.leading(to: view, constant: 10.0)
myView.mrk.trailing(to: view, constant: -10.0)
myView.mrk.bottom(to: view, constant: -10.0)

or even shorter using fillSuperview:

let edgeInsets = UIEdgeInsets(top: 10.0, left: 10.0, bottom: 10.0, right: 10.0)
myView.mrk.fillSuperview(edgeInsets)

Centering

myView.mrk.centerX(to: view)
myView.mrk.centerY(to: view)

or equivalent:

myView.mrk.center(to: view)

Measurements

Constraints for width and height:

myView.mrk.width(100)
myView.mrk.height(100)

Modify constraints

// Create a reference to the `NSLayoutConstraint` e.g. for height

let heightConstraint = myView.mrk.height(100)

...

// Update the height constant

heightConstraint.constant = 30.0

// Animate changes

UIView.animate(withDuration: 0.3) {
    self.view.layoutIfNeeded()
}

What to do next

• Writing tests

License

MarkerKit is available under the MIT license. See the LICENSE file for more info.