iOS：提醒用户特定地理位置区域（纬度，经度）

Question

我正在尝试为用户实现Geo location 的功能，我正在静态设置latitude 和longitude 信息，当应用程序启动时，如果用户在我出现的那个区域内一条消息“你已被联系到办公室”，否则“你要离开办公室”。我已经实现了下面的代码来实现这一点，我尝试通过步骤和车辆四处移动，但在这两种情况下它总是显示“你已经到达办公室”，但是我离那个位置 2 公里！我认为问题在于CLLocationManager委托中的地理数据比较。

- (void) startUpdateUserLocation
{
    if(!locationManager)
        locationManager = [[CLLocationManager alloc] init];

    locationManager.delegate = self;
    locationManager.distanceFilter = kCLDistanceFilterNone;
    locationManager.desiredAccuracy = kCLLocationAccuracyBestForNavigation;

//    [locationManager startUpdatingLocation];

    CLLocationCoordinate2D coord = CLLocationCoordinate2DMake(latitude, longitude);

    CLRegion *region = [[CLRegion alloc] initCircularRegionWithCenter:coord radius:kCLDistanceFilterNone identifier:@"identifier"];
    [locationManager startMonitoringForRegion:region];
}

- (void)viewDidLoad
{
    [super viewDidLoad];

    latitude = 23.076289;
    longitude = 72.508129;
}

- (void) viewDidAppear:(BOOL)animated
{
    [super viewDidAppear:animated];

    MKCoordinateRegion region;
    region.center = mapView.userLocation.coordinate;
    region.span = MKCoordinateSpanMake(0.25, 0.25);
    region = [mapView regionThatFits:region];
    [mapView setRegion:region animated:YES];

    lblCurrentCoords.text = [NSString stringWithFormat:@"lat %f lon %f",mapView.userLocation.coordinate.latitude,mapView.userLocation.coordinate.longitude];

    [self startUpdateUserLocation];
}

- (void)locationManager:(CLLocationManager *)manager
didEnterRegion:(CLRegion *)region __OSX_AVAILABLE_STARTING(__MAC_10_7,__IPHONE_4_0)
{
    [listOfPoints addObject:manager.location];
    [tablePoints reloadData];

    /*
     *  locationManager:didEnterRegion:
     *
     *  Discussion:
     *    Invoked when the user enters a monitored region.  This callback will be invoked for every allocated
     *    CLLocationManager instance with a non-nil delegate that implements this method.
     */

    lblLocationStatus.text = @"You're in office area!...";
}

- (void)locationManager:(CLLocationManager *)manager
didExitRegion:(CLRegion *)region __OSX_AVAILABLE_STARTING(__MAC_10_7,__IPHONE_4_0)
{
    /*
     *  locationManager:didExitRegion:
     *
     *  Discussion:
     *    Invoked when the user exits a monitored region.  This callback will be invoked for every allocated
     *    CLLocationManager instance with a non-nil delegate that implements this method.
     */

    lblLocationStatus.text = @"You're going out from office area!...";
}

- (void)locationManager:(CLLocationManager *)manager
didStartMonitoringForRegion:(CLRegion *)region __OSX_AVAILABLE_STARTING(__MAC_TBD,__IPHONE_5_0)
{
    /*
     *  locationManager:didStartMonitoringForRegion:
     *
     *  Discussion:
     *    Invoked when a monitoring for a region started successfully.
     */

    lblLocationStatus.text = @"Start monitoring...";
}

- (void)locationManager:(CLLocationManager *)manager
monitoringDidFailForRegion:(CLRegion *)region
withError:(NSError *)error __OSX_AVAILABLE_STARTING(__MAC_10_7,__IPHONE_4_0)
{
    /*
     *  locationManager:monitoringDidFailForRegion:withError:
     *
     *  Discussion:
     *    Invoked when a region monitoring error has occurred. Error types are defined in "CLError.h".
     */

    lblLocationStatus.text = @"Stop monitoring...";
}

我正在努力完成以下事情！

1. 如果用户输入了地理位置，他应该“警觉”。 --- 如何匹配位置？
2. 如果在该地理位置内四处走动，则代码应监控此活动！ --- 需要设置所需的精度属性吗？
3. 我希望我的代码不断检查用户地理位置，我该怎么做？ --- 需要调用NSTimer中的函数吗？

我在 SO 上发现了很多相同的问题，但没有人给出匹配的答案！有人请指导我是否朝着正确的方向前进，因为此代码未显示！ :)

Answer 1

听起来您应该改用区域监控，它会告诉您用户何时进入或退出圆形区域。使用startMonitoringForRegion: 设置它并实现CLLocationManagerDelegate 方法

– locationManager:didEnterRegion:
– locationManager:didExitRegion:
– locationManager:monitoringDidFailForRegion:withError:
– locationManager:didStartMonitoringForRegion:

如果您在输入错误的位置数据时遇到问题，请在locationManager:didUpdateLocations: 或locationManager:didUpdateToLocation:fromLocation: 中检查CLLocation 的年龄。如果超过 60 秒，请不要使用它。