我正在制作一个应用程序，它在UIImageView中显示gif，并从parse中加载gif。我偶然发现的问题是每当我加载一个Gif时，它会使用大约20 MB的内存，并且当我执行一个segue时，这个内存不会被分配。我从UIImageView中删除图像本身，但它仍然不释放内存。显示gif时出现巨大的内存使用Swift iOS

这是我用来显示GIF代码：

extension UIImage {

public class func gifWithData(data: NSData) -> UIImage? {

guard let source = CGImageSourceCreateWithData(data, nil) else {

print("SwiftGif: Source for the image does not exist")

return nil

}

return UIImage.animatedImageWithSource(source)

}

public class func gifWithName(name: String) -> UIImage? {

guard let bundleURL = NSBundle.mainBundle().URLForResource(name, withExtension: "gif") else {

print("SwiftGif: This image named \"\(name)\" does not exist")

return nil

}

guard let imageData = NSData(contentsOfURL: bundleURL) else {

print("SwiftGif: Cannot turn image named \"\(name)\" into NSData")

return nil

}

return gifWithData(imageData)

}

class func delayForImageAtIndex(index: Int, source: CGImageSource!) -> Double {

var delay = 0.1

// Get dictionaries

let cfProperties = CGImageSourceCopyPropertiesAtIndex(source, index, nil)

let gifProperties: CFDictionaryRef = unsafeBitCast(

CFDictionaryGetValue(cfProperties,

unsafeAddressOf(kCGImagePropertyGIFDictionary)),

CFDictionary.self)

// Get delay time

var delayObject: AnyObject = unsafeBitCast(

CFDictionaryGetValue(gifProperties,

unsafeAddressOf(kCGImagePropertyGIFUnclampedDelayTime)),

AnyObject.self)

if delayObject.doubleValue == 0 {

delayObject = unsafeBitCast(CFDictionaryGetValue(gifProperties,

unsafeAddressOf(kCGImagePropertyGIFDelayTime)), AnyObject.self)

}

delay = delayObject as! Double

if delay < 0.1 {

delay = 0.1 // Make sure they're not too fast

}

return delay

}

class func gcdForPair(var a: Int?, var _ b: Int?) -> Int {

// Check if one of them is nil

if b == nil || a == nil {

if b != nil {

return b!

} else if a != nil {

return a!

} else {

return 0

}

}

// Swap for modulo

if a < b {

let c = a

a = b

b = c

}

// Get greatest common divisor

var rest: Int

while true {

rest = a! % b!

if rest == 0 {

return b! // Found it

} else {

a = b

b = rest

}

}

}

class func gcdForArray(array: Array) -> Int {

if array.isEmpty {

return 1

}

var gcd = array[0]

for val in array {

gcd = UIImage.gcdForPair(val, gcd)

}

return gcd

}

class func animatedImageWithSource(source: CGImageSource) -> UIImage? {

let count = CGImageSourceGetCount(source)

var images = [CGImageRef]()

var delays = [Int]()

// Fill arrays

for i in 0..

// Add image

if let image = CGImageSourceCreateImageAtIndex(source, i, nil) {

images.append(image)

}

// At it's delay in cs

let delaySeconds = UIImage.delayForImageAtIndex(Int(i),

source: source)

delays.append(Int(delaySeconds * 1000.0)) // Seconds to ms

}

// Calculate full duration

let duration: Int = {

var sum = 0

for val: Int in delays {

sum += val

}

return sum

}()

// Get frames

let gcd = gcdForArray(delays)

var frames = [UIImage]()

var frame: UIImage

var frameCount: Int

for i in 0..

frame = UIImage(CGImage: images[Int(i)])

frameCount = Int(delays[Int(i)]/gcd)

for _ in 0..

frames.append(frame)

}

}

// Heyhey

let animation = UIImage.animatedImageWithImages(frames,

duration: Double(duration)/1000.0)

return animation

}

class func FinalFrame(source: CGImageSource) -> UIImage? {

let count = CGImageSourceGetCount(source)

var images = [CGImageRef]()

var delays = [Int]()

var finalFrame = UIImage()

// Fill arrays

for i in 0..

// Add image

if let image = CGImageSourceCreateImageAtIndex(source, i, nil) {

images.append(image)

}

// At it's delay in cs

let delaySeconds = UIImage.delayForImageAtIndex(Int(i),

source: source)

delays.append(Int(delaySeconds * 1000.0)) // Seconds to ms

}

// Get frames

let gcd = gcdForArray(delays)

var frames = [UIImage]()

var frame: UIImage

var frameCount: Int

for i in 0..

frame = UIImage(CGImage: images[Int(i)])

frameCount = Int(delays[Int(i)]/gcd)

for _ in 0..

frames.append(frame)

}

}

finalFrame = frames[frames.count-1]

return finalFrame

}

}

难道这是原因，我得到的内存问题？ 感谢任何帮助！

+0

两者GIF和APNG可以以低存储器请求数，像这样进行处理：http://stackoverflow.com/a/25478854/763355 –