Why are my images are not being cached in AlamofireImage? - ios

Question

I am clueless at the moment, I dont know why I am getting nil each time when I am trying to retrieve. I am passing the correct image data and identifier. Here's a little code
let photoCache = AutoPurgingImageCache(
memoryCapacity: 100 * 1024 * 1024,
preferredMemoryUsageAfterPurge: 60 * 1024 * 1024
)
func cacheImage(image: Image, urlString: String) {
print("Image size: \(image.size) and string as identifier: \(urlString)")
self.photoCache.addImage(image, withIdentifier: urlString)
}
func cachedImage(urlString: String) -> Image? {
print("What is url? : \(urlString)")
print("What we are actually returning? : \(self.photoCache.imageWithIdentifier(urlString))")
return self.photoCache.imageWithIdentifier(urlString)
}
Print for the cacheImage function: Image size: (2826.0, 3722.0) and string as identifier: http:www.somelink.com/DT199.jpg
Print for the cachedImage when I am trying retrieving it: what is the URL? : http:www.somelink.com/DT199.jpg What we are actually returning is : nil
I don't know why it is happening I tried it several times before and it worked perfectly. I also read about these functions, they don't return any boolean response through which we can get to know whether the image is in cache or not.
Later on, i tried using the download manager as well nothing happen still clueless. If any one can help me? here's the code
let imageDownloader = ImageDownloader(
configuration: ImageDownloader.defaultURLSessionConfiguration(),
downloadPrioritization: .FIFO,
maximumActiveDownloads: 15,
imageCache: AutoPurgingImageCache()
)
let downloader = imageDownloader
Alamofire.request(.GET, request, headers: headers)
.responseJSON { response in
if let JSON = response.result.value {
self.imagesArray = NSMutableArray()
self.imagesArray = JSON["results"] as! NSMutableArray
for results in self.imagesArray{
let URLRequest = NSURLRequest(URL: NSURL(string:results["url"] as! String)!)
downloader.downloadImage(URLRequest: URLRequest, filter: nil, completion: { response in
if response.response?.statusCode == 200{
print("In the house fetching url: \(results["url"] as! String)")
let image = response.result.value
print("Size of image: \(image?.size)")
let returnValue = downloader.imageCache?.addImage(image!, withIdentifier: results["url"] as! String)
print("return status: \(returnValue)")
if results .isEqual(self.imagesArray.lastObject){
self.activityIndicatorView.stopAnimating()
self.activityIndicatorView.hidden = true
let fic = self.imagesArray.firstObject
print("getting image for this url : \(fic!["url"] as! String)")
var imageC = UIImage()
imageC = (downloader.imageCache?.imageWithIdentifier(fic!["url"] as! String))!
self.ssImage.image = imageC
print("Image : \(imageC.size))")
}
}
})
}
}
}

Answer 1

Maybe you have to initialize your imageDownloader with the photoCache you used before to cache the images manually. The AutoPurgingImageCache isn't a shared instance. Only the UIImageView+AlamofireImage.swift extension has a af_sharedImageDownloader which keeps one AutoPurgingImageCache.
In dependence on your code example it should look like this:
let imageDownloader = ImageDownloader(
configuration: ImageDownloader.defaultURLSessionConfiguration(),
downloadPrioritization: .FIFO,
maximumActiveDownloads: 15,
imageCache: self.photoCache
)