swift-chainable-animations

A μ-framework which makes chaining UIView animations more simple and elegant.

Background

When using the UIView.animate api, you may find yourself using the completion to set up a new animation. This can quickly lead to code which is hard to read and suffers from the dreaded Pyramid Of Doom.

How to get it

Manually

Download https://github.com/DomainGroupOSS/swift-chainable-animations/blob/master/ChainableAnimations/UIViewAnimationExtensions.swift and add it to your project. Job done!

Carthage

git "DomainGroupOSS/swift-chainable-animations" "0.1.1"    

Cocoapods

pod "SwiftChainableAnimations", "0.1.1" 

Swift Package Manager

//TODO

Usage

ChainableAnimations is a single-file μ-framework which provides an alternate UIView api:

• Use .prepareAnimation(...) to define the first animation...
• ... and .then(...) any number of time afterwards to define a chain of linked animations, executed one after another.
• Animations will not be performed until you call .animate(...).
• Parameters for all functions follow the existing UIView.animate conventions and will do what you expect them to.

Before

UIView.animate(withDuration: 0.15, delay: 0.0, options: .curveEaseIn, animations: {
    self.titleImageView.transform = CGAffineTransform(scaleX: 1.2, y: 1.2)
}, completion: { _ in
    UIView.animate(withDuration: 0.4, delay: 0.0, options: .curveEaseOut, animations: {
        self.titleImageView.transform = CGAffineTransform.identity
    }, completion: nil)
})

After

import ChainableAnimations

UIView.prepareAnimation(withDuration: 0.15, options: .curveEaseIn) {
    self.titleImageView.transform = CGAffineTransform(scaleX: 1.2, y: 1.2)
}.then(withDuration: 0.4, options: .curveEaseOut) {
    self.titleImageView.transform = CGAffineTransform.identity
}.animate()

Before

UIView.animate(withDuration: stageDuration, delay: 0, options: .curveEaseIn, animations: stageOne) { _ in
    UIView.animate(withDuration: stageDuration, delay: 0, options: .curveEaseIn, animations: stageTwo, completion: { _ in
        UIView.animate(withDuration: stageDuration, delay: 0, options: .curveEaseIn, animations: stageThree, completion: nil)
    })
}

After

import ChainableAnimations

UIView
    .prepareAnimation(withDuration: stageDuration, delay: 0, options: .curveEaseIn, animations: stageOne)
    .then(withDuration: stageDuration, delay: 0, options: .curveEaseIn, animations: stageTwo)
    .then(withDuration: stageDuration, delay: 0, options: .curveEaseIn, animations: stageThree)
    .animate()