ios - 如何在Google Drive API中获得下载进度(快速5)

Question

我使用此功能从Google Drive API下载文件，并且希望获得下载进度。也许有人知道该怎么做？

func download(file: GTLRDrive_File) {
    let url = "https://www.googleapis.com/drive/v3/files/\(file.identifier!)?alt=media"
    let fetcher = drive.fetcherService.fetcher(withURLString: url)
    fetcher.beginFetch(completionHandler: { data, error in
        if let error = error {
            print(error.localizedDescription)
        }

        //Here I save data to the Documents
    })
}

我试图从fetcher.receivedProgressBlock获取它，但总是返回nil

Answer 1

解。实际适用于Swift 5:

func download(file: GTLRDrive_File) {
    let fileSize = file.size?.doubleValue //You need to fetch file size in your request q.fields = "kind,nextPageToken,files(mimeType,id,name,size)"
    let url = "https://www.googleapis.com/drive/v3/files/\(file.identifier!)?alt=media"
    let fetcher = drive.fetcherService.fetcher(withURLString: url)
    fetcher.beginFetch(completionHandler: { data, error in
        if let error = error {
            print(error.localizedDescription)
        }

        //Here I save data to the Documents
    })

    //Here you can get total bytes received (value is updated in real time)
    fetcher.receivedProgressBlock = { _, totalBytesReceived in
            guard let fileSize = fileSize else { return }
            let progress = Double(totalBytesReceived) / fileSize
            print(progress) //Here you can update UI (progress bar) or do something else
        }
}