[iOS]捕获用户位置:澄清

时间:2013-04-30 10:22:01

标签: ios objective-c cllocationmanager userlocation

我有一个应用程序可以捕获用户位置并将此信息发送到我的服务器。

我用:

启动了LocationManager服务
- (CLLocationManager *)locationManager {
    if (_locationManager == nil) {
        _locationManager = [[CLLocationManager alloc] init];
        _locationManager.delegate = self;
        isUpdatingLocation = NO;
    }
    return _locationManager; 
}

-(void) startLookingForLocation{

    [self locationManager].desiredAccuracy = kCLLocationAccuracyBest;
    [self locationManager].distanceFilter = 250;

    if([[self locationManager]respondsToSelector:@selector(setPausesLocationUpdatesAutomatically:)])
        [[self locationManager] setPausesLocationUpdatesAutomatically:YES];

    if([[self locationManager]respondsToSelector:@selector(setActivityType:) ])
        [[self locationManager] setActivityType:CLActivityTypeFitness];

    [[self locationManager] startUpdatingLocation];
    [[self locationManager] startUpdatingHeading];

    isUpdatingLocation = YES;
}

并停止:

-(void) stopLookingForLocation{

    [[self locationManager] stopUpdatingLocation];
    [[self locationManager] stopUpdatingHeading];

    isUpdatingLocation = NO;

}

所以,当我检测到用户位置的变化时:

- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation {

    [self setCurrentLocation:newLocation];

    BOOL isInBackground = NO;
    if ([UIApplication sharedApplication].applicationState == UIApplicationStateBackground)
    {
        isInBackground = YES;
    }

    if (isInBackground)
    {
        UIBackgroundTaskIdentifier bgTask = [[UIApplication sharedApplication]
                  beginBackgroundTaskWithExpirationHandler:
                  ^{
                      [[UIApplication sharedApplication] endBackgroundTask:bgTask];
                  }];

        // Send user-location to my server

        if (bgTask != UIBackgroundTaskInvalid)
        {
            [[UIApplication sharedApplication] endBackgroundTask:bgTask];
            bgTask = UIBackgroundTaskInvalid;
        }
    }
    else
    {
        // Send user-location to my server
    }

}

并且一切正常。 (我想)。

当app进入后台模式时,我在appDelegate中调用此方法     - (void)applicationDidEnterBackground:(UIApplication *)应用程序     {         [locationManager startMonitoringSignificantLocationChanges];     }

当app返回前台时:

- (void)applicationDidBecomeActive:(UIApplication *)application
{
    [locationManager stopMonitoringSignificantLocationChanges];
}

但我有些疑惑。这样,如果app处于关闭状态,我的应用程序会继续将位置发送到服务器吗?

如果我处于后台或前台状态时如何发送位置?

编辑: 我也设置了:

UIBackgroundModes     地点

1 个答案:

答案 0 :(得分:2)

不需要此代码,这将在后台激活您的应用程序很少有时间您必须在项目的info.plist中提及所需的后台模式,并且值应该是App寄存器以进行位置更新。

仅在info.plist中设置UIBackgroundModes位置,它在后台运行 这可能会对你有所帮助。

//In app deligate 

#pragma mark -
#pragma mark  GPS Service

//========== start GPS SERVICE ===========
-(void)startGpsService
{

    locationManager=[[CLLocationManager alloc] init];
    locationManager.delegate=self;
    locationManager.desiredAccuracy=kCLLocationAccuracyBest;
    locationManager.distanceFilter=10.0;
    [locationManager startUpdatingLocation];
    [self performSelectorInBackground:@selector(sendDataToServer) withObject:nil];
}

#pragma mark -
#pragma mark CLLocation Manager Delegates

- (void)locationManager:(CLLocationManager *)manager
didUpdateToLocation:(CLLocation *)newLocation
       fromLocation:(CLLocation *)oldLocation
{
      [self performSelectorInBackground:@selector(sendDataToServer) withObject:nil];

}

- (void)applicationDidEnterBackground:(UIApplication *)application
{
    // No need to do any thing 
   /* UIApplication *app = [UIApplication sharedApplication];
      UIBackgroundTaskIdentifier bgTask = 0;
      bgTask = [app beginBackgroundTaskWithExpirationHandler:^{
      [app endBackgroundTask:bgTask];
       }];
*/
}