EZAnchor

An easier way to code Autolayout

Language: Swift 4
Platform: iOS 9+
CocoaPods compatible
License: MIT

  • [x] Are you annoyed of coding .active = true while using Autolayout Anchors over and over again?
  • [x] Are you annoyed of coding such long constraint sentence refreshView.heightAnchor.constraint(equalToConstant: self.refreshViewHeight).isActive = true over and over again?

Now EZAnchor is definitely going to shorten your time of writing Autolayout Anchors by a simple installation.
Let's see how it works:

  • Anchor constraint to another anchor
//Traditional way
viewA.leadingAnchor.constraint(equalTo: viewB.leadingAnchor).isActive = true

//With EZAnchor
viewA.leading == viewB.leading
  • Anchor constraint to another anchor with constant
//Traditional way
viewA.leadingAnchor.constraint(equalTo: self.view.leadingAnchor, constant: 10).isActive = true

//With EZAnchor
viewA.leading == self.view.leading + 10
  • Anchor constraint to another anchor with negative constant
//Traditional way
viewA.leadingAnchor.constraint(equalTo: viewB.leadingAnchor, constant: -10).isActive = true

//With EZAnchor
viewA.leading == viewB.leading - 10
  • Anchor lessThanOrEqualTo another anchor
//Traditional way
viewA.leadingAnchor.constraint(lessThanOrEqualTo: viewB.leadingAnchor).isActive = true

//With EZAnchor
viewA.leading <= viewB.leading
  • Anchor greaterThanOrEqualTo another anchor
viewA.leadingAnchor.constraint(greaterThanOrEqualTo: viewB.leadingAnchor).isActive = true

//With EZAnchor
viewA.leading >= viewB.leading
  • Anchor lessThanOrEqualTo another anchor with constant
viewA.leadingAnchor.constraint(lessThanOrEqualTo: viewB.leadingAnchor, constant: 10).isActive = true

//With EZAnchor
viewA.leading <= viewB.leading + 10
  • Anchor greaterThanOrEqualTo another anchor with constant
//Traditional way
viewA.leadingAnchor.constraint(greaterThanOrEqualTo: viewB.leadingAnchor, constant: 10).isActive = true

//With EZAnchor
viewA.leading >= viewB.leading - 10
  • Anchor equalTo another anchor with constant and multiplier
//Traditional way
viewA.heightAnchor.constraint(equalTo: viewB.heightAnchor, multiplier: 0.1, constant: -10).isActive = true

//With EZAnchor
viewA.height == viewB.height * 0.1 - 10
  • Work with Priority
//With EZAnchor
viewA.leading == (viewB.leading + 0.1) ^ .defaultLow

Installation

Drag and drop

Directly drag EZAnchor and drop into your Xcode project.

CocoaPods

To integrate EZAnchor into your Xcode project using CocoaPods, specify it in your Podfile:

target 'MyApp' do
  pod 'EZAnchor'
end

Carthage

To integrate EZAnchor into your Xcode project using Carthage, specify it in your Cartfile:
coming soon

Run carthage update to build the framework and drag the built EZAnchor.framework into your Xcode project.

Demo

You can easily implement the following layout with very simple and clean code:

//set viewA's layout constraints
let viewA = UIView()
viewA.backgroundColor = UIColor.red
view.addEZSubview(viewA)
        
viewA.leading == view.leading + 5
viewA.trailing == view.trailing - 5
viewA.top == view.top + 15
viewA.centerX == view.centerX
viewA.height == view.height/2
        
//set viewB's layout constraints
let viewB = UIView()
viewB.backgroundColor = UIColor.yellow
view.addEZSubview(viewB)
        
viewB.top == viewA.bottom + 5
viewB.leading == viewA.leading
viewB.bottom == view.bottom - 5
viewB.trailing == view.centerX - 5

//set viewC's layout constraints        
let viewC = UIView()
viewC.backgroundColor = UIColor.green
view.addEZSubview(viewC)
        
viewC.top == viewB.top
viewC.bottom == viewB.bottom
viewC.leading == view.centerX + 5
viewC.trailing == viewA.trailing
        

Image of DemoScreenshot

Chaining function

Chaining way to code Autolayout with EZAnchor


viewA.setLeading(view.leading + 5)
     .setTrailing(view.trailing - 5)
     .setTop(view.top + 15)
     .setCenterX(view.centerX)
     .setHeight(view.height/2)


viewB.setTop(viewA.bottom + 5)
     .setLeading(viewA.leading)
     .setBottom(view.bottom - 5)
     .setTrailing(view.centerX - 5)

viewC.setTop(viewB.top)
     .setBottom(viewB.bottom)
     .setLeading(view.centerX + 5)
     .setTrailing(viewA.trailing)

Limitations

  1. Better to have some basic concept of anchors, familiar with coding anchors programmatically. If not please learn from this link : Programmatically Creating Constraints!

  2. Avoid defining custom UIControl or view has same name with height or width, there may have conflict with EZAnchor library

Others

WTF Autolayout will help you debug autolayout complaints.
Logo is generated with Shopify logo maker
Inspired by: PureLayout Stevia layout

Todo

  • [ ] Unit tests
  • [ ] UI Tests
  • [ ] CI
  • [ ] Fastlane

License

This code and tool is under the MIT License.

GitHub

https://github.com/alexliubj/EZAnchor