我正在下载一个视频,感谢downloadTaskWithURL,我用这段代码将它保存到我的画廊：
func saveVideoBis(fileStringURL:String){
print("saveVideoBis");
let url = NSURL(string: fileStringURL);
(NSURLSession.sharedSession().downloadTaskWithURL(url!) { (location:NSURL?,r:NSURLResponse?,e:NSError?) -> Void in
let mgr = NSFileManager.defaultManager()
let documentsPath = NSSearchPathForDirectoriesInDomains(.DocumentDirectory,.UserDomainMask,true)[0];
print(documentsPath);
let destination = NSURL(string: NSString(format: "%@/%@",documentsPath,url!.lastPathComponent!) as String);
print(destination);
try? mgr.moveItemAtPath(location!.path!,toPath: destination!.path!)
PHPhotoLibrary.requestAuthorization({ (a:PHAuthorizationStatus) -> Void in
PHPhotoLibrary.sharedPhotoLibrary().performChanges({
PHAssetChangeRequest.creationRequestForAssetFromVideoAtFileURL(destination!);
}) { completed,error in
if completed {
print(error);
print("Video is saved!");
self.sendNotification();
}
}
})
}).resume()
}
它在我的模拟器上工作得非常好,但在我的iPad上,即使打印(“视频已保存！”),视频也不会保存;出现.
你知道为什么吗？
我的控制台中也出现了该消息
Unable to create data from file (null)
解决方法
请通过以下代码检查评论：
Xcode 8•Swift 3
import UIKit
import Photos
class ViewController: UIViewController {
func downloadVideoLinkAndCreateAsset(_ videoLink: String) {
// use guard to make sure you have a valid url
guard let videoURL = URL(string: videoLink) else { return }
guard let documentsDirectoryURL = FileManager.default.urls(for: .documentDirectory,in: .userDomainMask).first else { return }
// check if the file already exist at the destination folder if you don't want to download it twice
if !FileManager.default.fileExists(atPath: documentsDirectoryURL.appendingPathComponent(videoURL.lastPathComponent).path) {
// set up your download task
URLSession.shared.downloadTask(with: videoURL) { (location,response,error) -> Void in
// use guard to unwrap your optional url
guard let location = location else { return }
// create a deatination url with the server response suggested file name
let destinationURL = documentsDirectoryURL.appendingPathComponent(response?.suggestedFilename ?? videoURL.lastPathComponent)
do {
try FileManager.default.moveItem(at: location,to: destinationURL)
PHPhotoLibrary.requestAuthorization({ (authorizationStatus: PHAuthorizationStatus) -> Void in
// check if user authorized access photos for your app
if authorizationStatus == .authorized {
PHPhotoLibrary.shared().performChanges({
PHAssetChangeRequest.creationRequestForAssetFromVideo(atFileURL: destinationURL)}) { completed,error in
if completed {
print("Video asset created")
} else {
print(error)
}
}
}
})
} catch { print(error) }
}.resume()
} else {
print("File already exists at destination url")
}
}
override func viewDidLoad() {
super.viewDidLoad()
downloadVideoLinkAndCreateAsset("https://www.yourdomain.com/yourmovie.mp4")
}
}
