AHAutoLayout-Swift

AHAutoLayout-Swift is a straightforward swift for more convinient auto layout management

Features

• Mathematical operations +, -, *, /, ==, >=, <= for creating NSAutoLayoutConstraint
• Convinient infix operations =>, ~~>, ~~~> for adding constraints in chain mode

Requirements

• iOS 7.0+
• Xcode 6.3

Communication

• If you need help, use Stack Overflow.
• If you'd like to ask a general question, use Stack Overflow.
• If you found a bug, open an issue.
• If you have a feature request, open an issue.
• If you want to contribute, submit a pull request.

Installation

**Embedded frameworks require a minimum deployment target of iOS 8

To use AHAutoLayout-Swift with a project targeting iOS 7, you must include all Swift files located inside the Source directory directly in your project. See the 'Source File' section for additional instructions.

CocoaPods

CocoaPods is a dependency manager for Cocoa projects.

CocoaPods 0.36 adds supports for Swift and embedded frameworks. You can install it with the following command:

$ gem install cocoapods

To integrate AHAutoLayout-Swift into your Xcode project using CocoaPods, specify it in your Podfile:

source 'https://github.com/CocoaPods/Specs.git'
platform :ios, '8.0'
use_frameworks!

pod 'AHAutoLayout-Swift', '~> 1.0.0'

Then, run the following command:

$ pod install

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Usage

Create an NSLayoutConstraints

import AHAutoLayout_Swift

view.left == parentView.left + 10
// is equal to 
NSLayoutConstraint(item: view, attribute: .Left, relatedBy: .Equal, toItem: parentView, attribute: .Left, multiplier: 1, constant:10


view.right >= parentView.right - 10
// is equal to 
NSLayoutConstraint(item: view, attribute: .Right, relatedBy: .GreaterThanOrEqual, toItem: parentView, attribute: .Right, multiplier: 1, constant:- 10

view.height == anotherView.height * 2
// is equal to 
NSLayoutConstraint(item: view, attribute: .Height, relatedBy: .Equal, toItem: anotherView, attribute: .Height, multiplier: 2, constant:0

view.height == anotherView.height / 2
// is equal to 
NSLayoutConstraint(item: view, attribute: .Height, relatedBy: .Equal, toItem: anotherView, attribute: .Height, multiplier: 0.5, constant:0


view.height == 100
// is equal to 
NSLayoutConstraint(item: view, attribute: .Height, relatedBy: .Equal, toItem: nil, attribute: .NotAnAttribute, multiplier: 1, constant:100

Add NSLayoutConstraints

// 4 NSLayoutConstraints were added and all their priority will be UILayoutPriorityRequired
self.view => self.redView.left == self.view.left + 10
        => self.redView.right == self.view.right - 10
        => self.redView.top == self.view.top + 30
        => self.redView.height == 100
        
// 4 NSLayoutConstraints were added 
// First two constraints' priorities will be UILayoutPriorityRequired
// Third constraint‘s priority will be UILayoutPriorityDefaultHigh
// Fourth constraint's priority will be UILayoutPriorityDefaultLow
self.view => self.redView.left == self.view.left + 10
        => self.redView.right == self.view.right - 10
        ~~> self.redView.top == self.view.top + 30
        ~~~> self.redView.height == 100
        
// If you want custom priority, you can write as belowing
var constaint = self.redView.left == self.view.left + 10
constraint.priority = UILayoutPriorityDefaultHigh - 1
self.view => constraint // => doesn't change priority

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FAQ

When should I use AHAutoLayout-Swift?

If you are writting iOS project with Swift, and you want to create UI by manually writting code instead of using Storyboar, but you still want to take the advantage of AutoLayout to save you do the math for calculating the frame, and use automatically handling dynamic content, AHAutoLayout-Swift may be one of your choice to save a lot of lines creating instance of NSLayoutConstraint, also let the code to be more cleaner and more straightforward.

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License

AHAutoLayout-Swift is released under the MIT license. See LICENSE for details.