ios - NSOperation和NSOperationQueue iOS的后台任务

Question

我想上传一些文件，即使应用程序进入后台，该文件也应继续。

目前，我正在从数据库中检索文件，而不是通过NSOperation将其添加到队列中，然后开始上载过程。

即使应用程序进入后台或前台，也应上传所有文件。
下面是单个任务的代码，任何人都可以给我提示我们如何使它能够用于上传许多文件。

UIApplication* application = [UIApplication sharedApplication];
bgTask = [application beginBackgroundTaskWithExpirationHandler:^{
  // Clean up any unfinished task business by marking where you
  // stopped or ending the task outright.

  [application endBackgroundTask: bgTask];
  bgTask = UIBackgroundTaskInvalid;
}];

Answer 1

为什么不尝试这样做呢？ ..我尚未尝试过，尝试后将发布更新

UIApplication* application = [UIApplication sharedApplication];
bgTask = [application beginBackgroundTaskWithExpirationHandler:^{
  // Clean up any unfinished task business by marking where you
  // stopped or ending the task outright.

  // Bring up your NSOperation queue instance here and block this thread until it is complete
  [queue waitUntilAllOperationsAreFinished];

  [application endBackgroundTask: bgTask];
  bgTask = UIBackgroundTaskInvalid;
}]; 

还应确保您有办法取消所有这些长期存在的后台操作

 bgTask = [application beginBackgroundTaskWithExpirationHandler:^{
        // Clean up any unfinished task business by marking where you.
        // stopped or ending the task outright.
        [queue cancelAllOperations];

        [application endBackgroundTask:endSessionTask];
        bgTask = UIBackgroundTaskInvalid;
    }];