ios - AFNetworking 2.0 跟踪文件上传进度

Question

我对 AFNetworking 2.0 比较陌生。使用下面的代码片段，我已经能够成功地将照片上传到我的网址。我想跟踪增量上传进度，但我找不到使用 2.0 版执行此操作的示例。我的应用程序是 iOS 7，所以我选择了 AFHTTPSessionManager。

谁能举例说明如何修改此代码段以跟踪上传进度？

AFHTTPSessionManager *manager = [AFHTTPSessionManager manager];

NSData *imageData = UIImageJPEGRepresentation([UIImage imageNamed:@"myimage.jpg"], 1.0);

[manager POST:@"http://myurl.com" parameters:dataToPost constructingBodyWithBlock:^(id<AFMultipartFormData> formData) {
    [formData appendPartWithFileData:imageData name:@"attachment" fileName:@"myimage.jpg" mimeType:@"image/jpeg"];
} success:^(NSURLSessionDataTask *task, id responseObject) {
    NSLog(@"Success %@", responseObject);
} failure:^(NSURLSessionDataTask *task, NSError *error) {
    NSLog(@"Failure %@, %@", error, [task.response description]);
}];

Answer 1

AFHTTPSession 的接口(interface)没有提供设置进度 block 的方法。相反，您必须执行以下操作:

// 1. Create `AFHTTPRequestSerializer` which will create your request.
AFHTTPRequestSerializer *serializer = [AFHTTPRequestSerializer serializer];

// 2. Create an `NSMutableURLRequest`.
NSMutableURLRequest *request =
    [serializer multipartFormRequestWithMethod:@"POST" URLString:@"http://www.myurl.com"
                                    parameters:dataToPost
                     constructingBodyWithBlock:^(id<AFMultipartFormData> formData) {
                       [formData appendPartWithFileData:imageData
                                                   name:@"attachment"
                                               fileName:@"myimage.jpg"
                                               mimeType:@"image/jpeg"];
                     }];

// 3. Create and use `AFHTTPRequestOperationManager` to create an `AFHTTPRequestOperation` from the `NSMutableURLRequest` that we just created.
AFHTTPRequestOperationManager *manager = [AFHTTPRequestOperationManager manager];
AFHTTPRequestOperation *operation =
    [manager HTTPRequestOperationWithRequest:request
                                     success:^(AFHTTPRequestOperation *operation, id responseObject) {
                                       NSLog(@"Success %@", responseObject);
                                     } failure:^(AFHTTPRequestOperation *operation, NSError *error) {
                                       NSLog(@"Failure %@", error.description);
                                     }];

// 4. Set the progress block of the operation.
[operation setUploadProgressBlock:^(NSUInteger __unused bytesWritten,
                                    long long totalBytesWritten,
                                    long long totalBytesExpectedToWrite) {
  NSLog(@"Wrote %lld/%lld", totalBytesWritten, totalBytesExpectedToWrite);
}];

// 5. Begin!
[operation start];

此外，您不必通过UIImage 读取图像，然后使用JPEG 再次压缩它以获得NSData。只需使用 +[NSData dataWithContentsOfFile:] 直接从您的包中读取文件。