bkayfitz-cara/swiftygif

High performance GIF engine

High performance & easy to use Gif engine

Features

• UIImage and UIImageView extension based
• Great CPU/Memory performances
• Control playback
• Allow control of display quality by using 'levelOfIntegrity'
• Allow control CPU/memory tradeoff via 'memoryLimit'

Installation

With CocoaPods

source 'https://github.com/CocoaPods/Specs.git'
use_frameworks!
pod 'SwiftyGif'

How to Use

Project files

As of now, Xcode xcassets folders do not recognize .gif as images. This means you need to put your .gif oustide of the assets. I recommend creating a group gif for instance.

Init

To use SwiftyGif you need 3 components:

• An UIImage which backs the gif data and cache it for efficient use.
• An UIImageView which hold to the UIImage gif and provide utility methods.
• A SwiftyGifManager which can hold one or several UIImageView using the same memory pool.

import SwiftyGif

let gifManager = SwiftyGifManager(memoryLimit:20)
let gif = UIImage(gifName: "MyImage.gif")
let imageview = UIImageView(gifImage: gif, manager: gifManager)
imageview.frame = CGRect(x: 0.0, y: 5.0, width: 400.0, height: 200.0)
view.addSubview(imageview)

Set

In case your UIImageView is already created (via Nib or Storyboards for instance), you can also set its Gif. You can do this multiple times, new parameters overwrite old ones.

let gifmanager = SwiftyGifManager(memoryLimit:20)
self.myImageView.setGifImage(gif, manager: gifManager) 

Level of integrity

Setting a lower level of integrity will allow for frame skipping, lowering both CPU and memory usage. This can be a godd option if you need to preview a lot of gifs at the same time.

let gif = UIImage(gifName: "MyImage.gif", levelOfIntegrity:0.5)

LoopCount

You can furthermore set a specific number of loops to your gif via loopCount. Default is -1, which translate to infinite.

self.myImageView.setGifImage(gif, manager: gifManager, loopCount:2)// The gif will loop 2 times

Controls

SwiftyGif offer various controls on the current UIImageView playing your gif file.

self.myImageView.startAnimatingGif()
self.myImageView.stopAnimatingGif()
self.myImageView.showFrameAtIndexDelta(delta: Int)
self.myImageView.showFrameAtIndex(index: Int)

To allow easy use of those controls, some utility methods are provided :

self.myImageView.isAnimatingGif() // Returns wether the gif is currently playing
self.myImageView.gifImage!.framesCount() // Returns number of frames for this gif

Delegate

You can declare a SwiftyGifDelegate to receive updates on the gif lifecycle. For instance, if you want your controller MyController to act as the delegate:

override func viewDidLoad() {
        super.viewDidLoad()
        self.imageView.delegate = self
}

Then simply add an extension:

extension MyController : SwiftyGifDelegate {

    func gifDidStart(sender: UIImageView) {
        print("gifDidStart")
    }
    
    func gifDidLoop(sender: UIImageView) {
        print("gifDidLoop")
    }
    
    func gifDidStop(sender: UIImageView) {
        print("gifDidStop")
    }
}

Default Manager

If you only need to display one gif here and there, you can use the SwiftyGifManager.defaultManager which will use a SwiftyGifManager singleton with a default memory pool of 50Mb.

Benchmark

Display 1 Image

	CPU Usage(average)	Memory Usage(average)
FLAnimatedImage	35%	9,5Mb
SwiftyGif	2%	18,4Mb
SwiftyGif(memoryLimit:10)	34%	9,5Mb

Display 6 Images

	CPU Usage(average)	Memory Usage(average)
FLAnimatedImage	65%	25,1Mb
SwiftyGif	22%	105Mb
SwiftyGif(memoryLimit:20)	45%	26Mb

Measured on an iPhone 6S, iOS 9.3.1 and Xcode 7.3.

Licence

SwiftyGif is released under the MIT license. See LICENSE for details.