使用UIWebView下载google驱动器文件

Question

我想从谷歌硬盘下载或导出文件。

1. 用户在UIWebView上登录google云端硬盘
2. 谷歌云端硬盘开放，用户选择任何特定文件，我有一个特定选定文件的下载链接。
3. 我在以下代码中使用该链接代替@“Google Drive文件Url”：

- （BOOL）webView：（UIWebView *）awebView shouldStartLoadWithRequest：（NSURLRequest *）请求navigationType：（UIWebViewNavigationType）navigationType {

if(navigationType == UIWebViewNavigationTypeLinkClicked)
{
    GTMHTTPFetcher *fetcher =
    [self.driveService.fetcherService fetcherWithURLString:@"Google Drive file Url"];

    [fetcher beginFetchWithCompletionHandler:^(NSData *data, NSError *error)
    {
         if (error == nil)
         {
             NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);

             NSString *documentsDirectoryPath = [paths objectAtIndex:0];

             NSString *filePath = [documentsDirectoryPath stringByAppendingPathComponent:@"dream.mp3"];
             [data writeToFile:filePath atomically:YES];
         }
         else
         {
             NSLog(@"An error occurred: %@", error);
         }
     }];
}

}