iOS Concurrency with GCD & Operations
About this episode
See forum comments
Mark complete
Next episode: 06. The Right Way to Download Images
Leave a rating/review
Heads up... You’re accessing parts of this content for free, with some sections shown as text.
Heads up... You’re accessing parts of this content for free, with some sections shown as text.
Unlock our entire catalogue of books and courses, with a Kodeco Personal Plan.
Unlock now
Challenge: A Better Way to Download Images
In the first episode, I showed you the sample app for this course. It’s unresponsive to user interaction because the image downloads all happen on the main thread, which should only be used for user interface tasks.
[weak self] in
guard let self else { return }
store.downloadImageOffMainQueue(index: image.id) // change On to Off
DispatchQueue.global(qos: .utility).async {
}
DispatchQueue.global(qos: .utility).async { [weak self] in
guard let self else { return }
}
if let data = try? Data(contentsOf: self.images[index].url),
let decodedImage = UIImage(data: data) {
images[index].image = decodedImage
}
DispatchQueue.main.async {
self.images[index].image = decodedImage
}