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@marcos1262
Last active October 27, 2018 14:06
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Asynchronous download of images and saving in caches directory
extension UIImageView {
//Use this function with the imageview
func loadImageUsingCacheWithUrlString(_ url: String?) {
guard let url = url else {
self.image = UIImage(named: "default")
return
}
let imageName = url.split(separator: "/").last! as NSString
let fileManager = FileManager.default
let diskPaths = NSSearchPathForDirectoriesInDomains(.cachesDirectory, .userDomainMask, true)
let cacheDirectory = diskPaths[0] as String
let diskPath = cacheDirectory.appending(imageName as String)
//check cache for image first
if fileManager.fileExists(atPath: diskPath) {
self.image = UIImage(contentsOfFile: diskPath)
return
}
//otherwise fire off a new download
URLSession.shared.dataTask(with: URL(string: url)!, completionHandler: { (data, response, error) in
guard error == nil else {
print("Image download error:", error?.localizedDescription ?? "")
return
}
DispatchQueue.main.async {
if let data = data, let image = UIImage(data: data) {
try? data.write(to: URL(fileURLWithPath: diskPath), options: .atomic)
self.image = image
}
}
}).resume()
}
}
extension UIImageView {
func downloadedFrom(url: URL, contentMode mode: UIView.ContentMode = .scaleAspectFit) {
contentMode = mode
URLSession.shared.dataTask(with: url) { (data, response, error) in
guard
let httpURLResponse = response as? HTTPURLResponse, httpURLResponse.statusCode == 200,
let mimeType = response?.mimeType, mimeType.hasPrefix("image"),
let data = data, error == nil,
let image = UIImage(data: data)
else { return }
DispatchQueue.main.async() {
self.image = image
}
}.resume()
}
func downloadedFrom(link: String, contentMode mode: UIView.ContentMode = .scaleAspectFit) {
guard let url = URL(string: link) else { return }
downloadedFrom(url: url, contentMode: mode)
}
}
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