Question

我尝试移植以下Objective-c代码

[transferUtility
 enumerateToAssignBlocksForUploadTask:^(AWSS3TransferUtilityUploadTask *uploadTask, __autoreleasing AWSS3TransferUtilityUploadProgressBlock *uploadProgressBlockReference, __autoreleasing AWSS3TransferUtilityUploadCompletionHandlerBlock *completionHandlerReference) {
     NSLog(@"%lu", (unsigned long)uploadTask.taskIdentifier);

     // Use `uploadTask.taskIdentifier` to determine what blocks to assign.

     *uploadProgressBlockReference = // Reassign your progress feedback block.
     *completionHandlerReference = // Reassign your completion handler.
 }
 downloadTask:^(AWSS3TransferUtilityDownloadTask *downloadTask, __autoreleasing AWSS3TransferUtilityDownloadProgressBlock *downloadProgressBlockReference, __autoreleasing AWSS3TransferUtilityDownloadCompletionHandlerBlock *completionHandlerReference) {
     NSLog(@"%lu", (unsigned long)downloadTask.taskIdentifier);

     // Use `downloadTask.taskIdentifier` to determine what blocks to assign.

     *downloadProgressBlockReference =  // Reassign your progress feedback block.
     *completionHandlerReference = // Reassign your completion handler.
 }];

到Swift 3

        transferUtility.enumerateToAssignBlocks(forUploadTask: { (uploadTask:AWSS3TransferUtilityUploadTask, progress:AutoreleasingUnsafeMutablePointer<(@convention(block) (AWSS3TransferUtilityTask, Progress) -> Void)?>?, error: AutoreleasingUnsafeMutablePointer<(@convention(block) (AWSS3TransferUtilityUploadTask, Error?) -> Void)?>?) in

                        let progressPointer = AutoreleasingUnsafeMutablePointer<AWSS3TransferUtilityProgressBlock?>(&self.progressBlock)
                        let completionPointer = AutoreleasingUnsafeMutablePointer<AWSS3TransferUtilityUploadCompletionHandlerBlock?>(&self.completionHandler)

                        progress = progressPointer



    }, downloadTask: nil)

我得到的是进步是一个让我不变的，我无法分配它。

如何解决？

Answer 1

您可以分配指针，如下面的代码所示：

AWSS3TransferUtility.default().enumerateToAssignBlocks(forUploadTask: { (uploadTask:AWSS3TransferUtilityUploadTask, uploadProgressBlockReference:AutoreleasingUnsafeMutablePointer<(@convention(block) (AWSS3TransferUtilityTask, Progress) -> Void)?>?, completionHandlerReference: AutoreleasingUnsafeMutablePointer<(@convention(block) (AWSS3TransferUtilityUploadTask, Error?) -> Void)?>?) in
    print("Hello, world")

    uploadProgressBlockReference?.pointee = {(task:AWSS3TransferUtilityTask, progress:Progress) -> Void in
        print("Fraction completed:  \(progress.fractionCompleted)")
    }
}, downloadTask: nil)

Swift 3：无法分配给AutoreleasingUnsafeMutablePointer

1 个答案: