ios - Swift 相当于 "[[transferManager download:downloadRequest] continueWithExecutor:[AWSExecutor mainThreadExecutor] withBlock:^id(AWSTask *task)"

Question

是否有 Swift 3.0 等同于:

[[transferManager download:downloadRequest] continueWithExecutor:[AWSExecutor mainThreadExecutor] withBlock:^id(AWSTask *task)

这是 Objective-C 实现(在 S3 iOS documentation 上我找不到 Swift 示例)。

Objective-C 代码(来自 AWS 文档):

     [[transferManager download:downloadRequest] continueWithExecutor:[AWSExecutor mainThreadExecutor] withBlock:^id(AWSTask *task) {

     NSLog(@"Task is continuing..");

     if (task.error){
     if ([task.error.domain isEqualToString:AWSS3TransferManagerErrorDomain]) {
     switch (task.error.code) {
     case AWSS3TransferManagerErrorCancelled:
     case AWSS3TransferManagerErrorPaused:
     break;

     default:
     NSLog(@"Error: %@", task.error);
     break;
     }
     } else {
     // Unknown error.
     NSLog(@"Error: %@", task.error);
     }
     }

     if (task.result) {
     // File downloaded successfuly
     NSLog(@"File downloaded successfuly");
     AWSS3TransferManagerDownloadOutput *downloadOutput = task.result;

     // Put this in hte right place
     //self.imageView.image = [UIImage imageWithContentsOfFile:downloadingFilePath];

     //File downloaded successfully.
     }
     return nil;
     }];

Answer 1

应该是 transferManager.download(downloadRequest).continueWithBlock({ (task) -> AnyObject!in

您还可以找到 Swift 翻译 here :

func download(downloadRequest: AWSS3TransferManagerDownloadRequest) {
        switch (downloadRequest.state) {
        case .NotStarted, .Paused:
            let transferManager = AWSS3TransferManager.defaultS3TransferManager()
            transferManager.download(downloadRequest).continueWithBlock({ (task) -> AnyObject! in
                if let error = task.error {
                    if error.domain == AWSS3TransferManagerErrorDomain as String
                        && AWSS3TransferManagerErrorType(rawValue: error.code) == AWSS3TransferManagerErrorType.Paused {
                            print("Download paused.")
                    } else {
                        print("download failed: [\(error)]")
                    }
                } else if let exception = task.exception {
                    print("download failed: [\(exception)]")
                } else {
                    dispatch_async(dispatch_get_main_queue(), { () -> Void in
                        if let index = self.indexOfDownloadRequest(self.downloadRequests, downloadRequest: downloadRequest) {
                            self.downloadRequests[index] = nil
                            self.downloadFileURLs[index] = downloadRequest.downloadingFileURL

                            let indexPath = NSIndexPath(forRow: index, inSection: 0)
                            self.collectionView.reloadItemsAtIndexPaths([indexPath])
                        }
                    })
                }
                return nil
            })

            break
        default:
            break
        }
    }