错误域= AVFoundationErrorDomain代码= -11800

Question

我正在尝试下载HLS视频以供离线播放。没有调用任何委托函数，但

-(void)URLSession:(NSURLSession *)session task:(NSURLSessionTask *)task didCompleteWithError:(NSError *)error {}

并显示以下错误：

  

Error Domain = AVFoundationErrorDomain代码= -11800“该操作可能   未完成” UserInfo = {NSLocalizedFailureReason =未知错误   发生（-12780），NSLocalizedDescription =无法执行该操作   完成}

我的代码如下：

        - (void)viewDidLoad {
            [super viewDidLoad];
            // Do any additional setup after loading the view, typically from a nib.

            [self setupAssetDownloader];
        }

        - (void)setupAssetDownloader {



            NSURL *assetURL = [NSURL fileURLWithPath:@"http://devimages.apple.com/iphone/samples/bipbop/bipbopall.m3u8"];
            AVURLAsset *hlsAsset = [AVURLAsset assetWithURL:assetURL];


            urlSessionConfiguration = [NSURLSessionConfiguration backgroundSessionConfigurationWithIdentifier:@"assetDowloadConfigIdentifier"];

            //MyDownloadDelegate *delegate = [[MyDownloadDelegate alloc] init];


            avAssetDownloadSession = [AVAssetDownloadURLSession sessionWithConfiguration:urlSessionConfiguration assetDownloadDelegate:self delegateQueue:[NSOperationQueue mainQueue]];

            // Download movie
            avAssetDownloadTask = [avAssetDownloadSession assetDownloadTaskWithURLAsset:hlsAsset assetTitle:@"cbvideo" assetArtworkData:nil options:nil];

            //@{AVAssetDownloadTaskMinimumRequiredMediaBitrateKey : @(300000)}


            [avAssetDownloadTask resume];

            restoredAsset = avAssetDownloadTask.URLAsset;
            AVPlayerItem *playerItem = [AVPlayerItem
                                        playerItemWithAsset:restoredAsset];

            //AVPlayerItem *playerItem = [[AVPlayerItem alloc] initWithAsset:avAssetDownloadTask.URLAsset];
            AVPlayer *player = [[AVPlayer alloc ] initWithPlayerItem:playerItem];
            AVPlayerLayer *playerLayer = [[AVPlayerLayer alloc ] init];
            [playerLayer setPlayer:player];
            [playerLayer setFrame:self.view.frame];
            [self.view.layer addSublayer:playerLayer];
            [player play];
        }

        #pragma mark - AVAssetDownloadDelegate


        - (void)URLSession:(NSURLSession *)session task:(NSURLSessionTask *)task didCompleteWithError:(NSError *)error {


        }

        - (void)URLSession:(NSURLSession *)session assetDownloadTask:(AVAssetDownloadTask *)assetDownloadTask didResolveMediaSelection:(AVMediaSelection *)resolvedMediaSelection {

        }
        - (void)URLSession:(NSURLSession *)session assetDownloadTask:(AVAssetDownloadTask *)assetDownloadTask didLoadTimeRange:(CMTimeRange)timeRange totalTimeRangesLoaded:(NSArray<NSValue *> *)loadedTimeRanges timeRangeExpectedToLoad:(CMTimeRange)timeRangeExpectedToLoad {
            NSInteger percent = 0;
            for (NSValue *value in loadedTimeRanges) {
                CMTimeRange timeRange = [value CMTimeRangeValue];
                percent += CMTimeGetSeconds(timeRange.duration) / CMTimeGetSeconds(timeRangeExpectedToLoad.duration);
            }
            percent *= 100;
            NSLog(@"Progress: %ld", (long)percent);
        }

        - (void)URLSession:(NSURLSession *)session assetDownloadTask:(AVAssetDownloadTask *)assetDownloadTask didFinishDownloadingToURL:(NSURL *)location {
            NSString *localPath = location.relativePath;
            NSLog(@"localPath: %@", localPath);
            // TODO: Play downloaded file
            // IMPORTANT: Don't move this file to another location.
        }