当应用程序进入iphone的背景时，如何在中对任务进行计数

即使应用程序在iPhone iOS中退出活动状态时进入后台，我如何运行任务直到任务完成。

首先，我们需要检查设备是否支持多任务处理

if([UIDevice currentDevice]respondsToSelector:@selector(isMultitaskingSupported)){

  //  If the device supports Multitasking we can run the task as :-

    UIBackgroundTaskIdentifier bgTask;

    bgTask=[[UIApplication sharedApplication] beginBackgroundTaskWithExpirationHandler:^{
        [[UIApplication sharedApplication] endBackgroundTask:bgTask];
    }];

    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0ul), ^{
        for(double i=0; i<99999; i++)
            NSLog(@"Backgroudn quee");

        [[UIApplication sharedApplication] endBackgroundTask:bgTask];
    });
}

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首先，我们需要检查设备是否支持多任务处理

if([UIDevice currentDevice]respondsToSelector:@selector(isMultitaskingSupported)){

  //  If the device supports Multitasking we can run the task as :-

    UIBackgroundTaskIdentifier bgTask;

    bgTask=[[UIApplication sharedApplication] beginBackgroundTaskWithExpirationHandler:^{
        [[UIApplication sharedApplication] endBackgroundTask:bgTask];
    }];

    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0ul), ^{
        for(double i=0; i<99999; i++)
            NSLog(@"Backgroudn quee");

        [[UIApplication sharedApplication] endBackgroundTask:bgTask];
    });
}

---

这是答案还是你在补充问题？谢谢我找到的答案，这是答案还是你在补充问题？谢谢我找到的答案