iOS 上的 Google Maps SDK（不是模拟器！），myLocation 为 0.000000

Question

编辑：这不一定与模拟器有关，带有 Debug->Location 的东西。无论我是在模拟器上还是在真机上，它都会显示 0.000000。

我正在使用谷歌地图尝试制作一个可以根据我当前位置执行操作的应用。

当我打开应用程序时，地图上的蓝点位置在我的实际（正确）位置，但我放置在“myLocation”处的标记位于 0.000000,0.000000（这也是打印出来的值）安慰）

当我打开应用程序和/或执行某些操作以获取蓝点所在位置的实时坐标时，如何使标记的位置位于当前位置？ （这样我就可以随时访问实时纬度和经度）

提前致谢！

这是我的代码：

#import "MyViewController.h"
#import <GoogleMaps/GoogleMaps.h>


@interface MyViewController ()
@property (nonatomic, readwrite) NSString *coord;
@end

@implementation MyViewController

GMSMapView *mapView_;


- (void)viewDidLoad
{
    [super viewDidLoad];
    [self.view layoutIfNeeded];

    // Do any additional setup after loading the view, typically from a nib.
    // Create a GMSCameraPosition that tells the map to display the
    // coordinate -33.86,151.20 at zoom level 6.
    CLLocation *myLocation = mapView_.myLocation;
    GMSCameraPosition *camera = [GMSCameraPosition     cameraWithLatitude:myLocation.coordinate.latitude
                                                            longitude:myLocation.coordinate.longitude
                                                             zoom:6];
mapView_ = [GMSMapView mapWithFrame:CGRectZero camera:camera];
mapView_.myLocationEnabled = YES;


self.view = mapView_;




// Creates a marker in the center of the map.
GMSMarker *marker = [[GMSMarker alloc] init];
//    marker.position = CLLocationCoordinate2DMake(-33.86, 151.20);
    marker.position = CLLocationCoordinate2DMake(myLocation.coordinate.latitude,     myLocation.coordinate.longitude);
marker.title = @"Current:";
float lat = mapView_.myLocation.coordinate.latitude;
float lon = mapView_.myLocation.coordinate.longitude;
_coord = [NSString stringWithFormat:@"%f %f",lat,lon];
printf("%f %f",lat,lon);
marker.snippet = (_coord);
marker.map = mapView_;
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}





@end

Answer 1

#import "ViewController.h"
#import <GoogleMaps/GoogleMaps.h>

@interface ViewController () <GMSMapViewDelegate>
{
 GMSMapView *mapView_;
}
@end

@implementation ViewController

- (void)didReceiveMemoryWarning
{
   [super didReceiveMemoryWarning];
   // Dispose of any resources that can be recreated.
}

- (void)viewWillAppear:(BOOL)animated
{
   [mapView_ addObserver:self forKeyPath:@"myLocation" options:0 context:nil];
}

- (void)dealloc
{
    [mapView_ removeObserver:self forKeyPath:@"myLocation"];
}

- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context
{
    if([keyPath isEqualToString:@"myLocation"])
    {
       CLLocation *location = [object myLocation];

        NSLog(@"Location, %@,", location);

        CLLocationCoordinate2D target =
        CLLocationCoordinate2DMake(location.coordinate.latitude, location.coordinate.longitude);

        [mapView_ animateToLocation:target];
        [mapView_ animateToZoom:17];
    }
}

- (void)viewDidLoad
{
    [super viewDidLoad];

    GMSCameraPosition *cam = [GMSCameraPosition cameraWithLatitude:mapView_.myLocation.coordinate.latitude longitude:mapView_.myLocation.coordinate.longitude zoom:15];
    mapView_ = [GMSMapView mapWithFrame:CGRectMake(20, 20, self.view.frame.size.width, self.view.frame.size.height - 64) camera:cam];

   self.view = mapView_;

    mapView_.delegate = self;

    mapView_.userInteractionEnabled = YES;
    mapView_.myLocationEnabled = YES;

    mapView_.mapType = kGMSTypeNormal;
    mapView_.indoorEnabled = YES;
    mapView_.accessibilityElementsHidden = NO;

    mapView_.settings.scrollGestures = YES;
    mapView_.settings.zoomGestures = YES;
    mapView_.settings.tiltGestures = YES;
    mapView_.settings.rotateGestures = YES;

    mapView_.settings.compassButton = YES;
    mapView_.settings.myLocationButton = YES;
    mapView_.settings.indoorPicker = YES;

}

Answer 2

为此，您需要 CLLocationManger 类的帮助

在 .h 文件中

CLLocationManager *currentLocationManager;
CLLocation *myLocation ;

输入 .m 文件

#import <CoreLocation/CoreLocation.h>


- (void)viewDidLoad
{
    [super viewDidLoad];
    [self.view layoutIfNeeded];

currentLocationManager = [[CLLocationManager alloc] init];
    currentLocationManager.desiredAccuracy = kCLLocationAccuracyBest;
    currentLocationManager.distanceFilter = DISTANCE_FILTER_VALUE_STATIONARY;
    [self.currentLocationManager setDelegate:self];
    [currentLocationManager startUpdatingLocation];

}

#pragma mark
#pragma mark for Location manager Delegate Methods

- (void)locationManager:(CLLocationManager *)manager
     didUpdateLocations:(NSArray *)locations {

myLocation = [locations lastObject];

// Now create maker on current location
GMSMarker *marker = [[GMSMarker alloc] init];
marker.position = myLocation.coordinate;
marker.title = @"Current:";
float lat = mapView_.myLocation.coordinate.latitude;
float lon = mapView_.myLocation.coordinate.longitude;
_coord = [NSString stringWithFormat:@"%f %f",lat,lon];
printf("%f %f",lat,lon);
marker.snippet = (_coord);
marker.map = mapView_;

}

这会在当前位置创建一个标记。您将根据位置管理器上设置的“距离过滤器”和“准确性”获得位置更新。