如果我在完成之前退出页面,如何取消 URLSession.shared.dataTask?
How can I cancel the URLSession.shared.dataTask if I exit the page before it completes?
根据的推荐,我可以进行如下异步下载,在viewDidLoad
期间调用。
func loadItems(tuple : (name : String, imageURL : URL)) {
print("Download Started")
URLSession.shared.dataTask(with: tuple.imageURL, completionHandler :
{ data, response, error in
guard let data = data, error == nil else { return }
print(response?.suggestedFilename ?? tuple.imageURL.lastPathComponent)
print("Download Finished")
DispatchQueue.main.async() { [weak self] in
self?.displayFlag(data: data, title: tuple.name)
}
}).resume()
}
一切正常。我的问题是,如果下载速度慢,我退出页面,如何以及在哪里(viewDidUnload
?看起来已经被弃用了)我可以取消获取(图像下载)任务吗?
保存 URLSessionTask
引用:
private weak var task: URLSessionTask?
func loadItems(name: String, url: URL) {
let task = URLSession.shared.dataTask(with: url) { [weak self] data, response, error in
guard let data = data, error == nil else { return }
print(response?.suggestedFilename ?? url.lastPathComponent)
print("Download Finished")
DispatchQueue.main.async {
self?.displayFlag(data: data, title: name)
}
}
task.resume()
self.task = task
}
然后,解雇时,cancel
它:
deinit {
task?.cancel()
}
根据的推荐,我可以进行如下异步下载,在viewDidLoad
期间调用。
func loadItems(tuple : (name : String, imageURL : URL)) {
print("Download Started")
URLSession.shared.dataTask(with: tuple.imageURL, completionHandler :
{ data, response, error in
guard let data = data, error == nil else { return }
print(response?.suggestedFilename ?? tuple.imageURL.lastPathComponent)
print("Download Finished")
DispatchQueue.main.async() { [weak self] in
self?.displayFlag(data: data, title: tuple.name)
}
}).resume()
}
一切正常。我的问题是,如果下载速度慢,我退出页面,如何以及在哪里(viewDidUnload
?看起来已经被弃用了)我可以取消获取(图像下载)任务吗?
保存 URLSessionTask
引用:
private weak var task: URLSessionTask?
func loadItems(name: String, url: URL) {
let task = URLSession.shared.dataTask(with: url) { [weak self] data, response, error in
guard let data = data, error == nil else { return }
print(response?.suggestedFilename ?? url.lastPathComponent)
print("Download Finished")
DispatchQueue.main.async {
self?.displayFlag(data: data, title: name)
}
}
task.resume()
self.task = task
}
然后,解雇时,cancel
它:
deinit {
task?.cancel()
}