- (void)applicationDidEnterBackground:(UIApplication *)application {

    //控制定时器不被kill

    UIApplication * app = [UIApplication sharedApplication];

    __block UIBackgroundTaskIdentifier bgTask;

    bgTask = [app beginBackgroundTaskWithExpirationHandler:^{

        dispatch_async(dispatch_get_main_queue(), ^{

            if (bgTask != UIBackgroundTaskInvalid) {

                bgTask = UIBackgroundTaskInvalid;

            }

        });

    }];

    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{

        dispatch_async(dispatch_get_main_queue(), ^{

            if (bgTask != UIBackgroundTaskInvalid) {

                bgTask = UIBackgroundTaskInvalid ;

            }

        });

    });

}

{

    //全局计时器

    NSTimer * timer;

}

-(void)turnOnTimer{

    //14400.0 秒调用一次

    timer = [NSTimer scheduledTimerWithTimeInterval:14400.0 target:self selector:@selector(pushGPSdata) userInfo:nil repeats:YES];

    [[NSRunLoop currentRunLoop] addTimer:timer forMode:NSRunLoopCommonModes];

}

-(void)pushGPSdata{

    //_dicUrl 全局保存定位信息

    NSString * cityName = [NSString stringWithFormat:@"%@",_dicUrl[@"cityName"]];

    NSString * latitude = [NSString stringWithFormat:@"%@",_dicUrl[@"latitude"]];

    NSString * longitude = [NSString stringWithFormat:@"%@",_dicUrl[@"longitude"]];

    if (cityName.length !=0&&latitude.length !=0&&longitude.length !=0) {

        [self pushGPS:_dicUrl];

    }

}

-(void)pushGPS:(NSMutableDictionary*)dic{

    [com afPostRequestWithUrlString:trail_Url parms:dic finishedBlock:^(id responseObj) {

        NSDictionary *dic = [NSJSONSerialization JSONObjectWithData:responseObj options:NSJSONReadingMutableLeaves error:nil];

        NSLog(@"%@",dic[@"message"]);

        NSString * userStatus = [NSString stringWithFormat:@"%@",dic[@"success"]];

        if ([userStatus isEqualToString:@"1"]) {

            NSLog(@"GPS成功");

        }else{

            NSLog(@"GPS失败");

        }

    } failedBlock:^(NSString *errorMsg) {

    }];

}