             self.base.downloadProgress { progress in
                 let rxProgress = RxProgress(bytesWritten: progress.completedUnitCount,
                                             totalBytes: progress.totalUnitCount)
-                observer.onNext(rxProgress)
+                observer.on(.next(rxProgress))
                 if rxProgress.bytesWritten >= rxProgress.totalBytes {
-                    observer.onCompleted()
+                    observer.on(.completed)
                 }
             }
             return Disposables.create()

            self.base.downloadProgress { progress in
                let rxProgress = RxProgress(bytesWritten: progress.completedUnitCount,
                                            totalBytes: progress.totalUnitCount)
                observer.onNext(rxProgress)
                if rxProgress.bytesWritten >= rxProgress.totalBytes {
                    observer.onCompleted()
                }
            }
            return Disposables.create()

                case .success(let result):
                    if let httpResponse = packedResponse.response {
                        observer.on(.next(httpResponse, result))
                        observer.on(.completed)
                    }
                    else {
                        observer.on(.error(RxAlamofireUnknownError))
                    }
                case .failure(let error):
                    observer.on(.error(error as Error))
                }
