Question

我的应用上有用户位置，但如何在当前用户位置删除注释？我是否必须获得长期＆amp; lat的用户位置和删除注释的方式？或者我该怎么做？

Answer 1

首先导入必要的框架（CoreLocation和MapKit）。
然后创建Objective-C NSObject类Annotation

设置其.h：

#import <Foundation/Foundation.h>

#import <CoreLocation/CoreLocation.h>

#import <MapKit/MapKit.h>

@interface Annotation : NSObject <MKAnnotation> 

@property (nonatomic) CLLocationCoordinate2D coordinate;
@property (nonatomic, copy) NSString *title;
@property (nonatomic, copy) NSString *subtitle;

@end

设置其.m：

#import "Annotation.h"

@implementation Annotation
@synthesize coordinate, title, subtitle;

@end

设置viewDidLoad

   if ([CLLocationManager locationServicesEnabled]) {

   locationManager = [[CLLocationManager alloc] init];

   [locationManager setDelegate:self];

   [locationManager setDesiredAccuracy: kCLLocationAccuracyBestForNavigation];

   [locationManager startUpdatingLocation];

   }

  self.mapView.delegate = self;

设置didUpdateToLocation

   // IMPORT ANNOTATION

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


   [locationManager stopUpdatingLocation];

   double miles = 3.10686;
   double scalingFactor = ABS((cos(2 * M_PI * newLocation.coordinate.latitude / 360.0)));

   MKCoordinateSpan span;

   span.latitudeDelta = miles/69.0;
   span.longitudeDelta = miles/(scalingFactor * 69.0);

   MKCoordinateRegion region;
   region.span = span;
   region.center = newLocation.coordinate;

   [self.mapView setRegion:region animated:YES];

   Annotation *annot = [[Annotation alloc] init];
   annot.coordinate = newLocation.coordinate;

   [self.mapView addAnnotation:annot];

     }

Answer 2

最简单的方法是在showsUserLocation上将YES设置为MKMapView并实施

- (void)mapView:(MKMapView *)mapView didUpdateUserLocation:(MKUserLocation *)userLocation {
    MKCoordinateRegion region = MKCoordinateRegionMake(userLocation.location.coordinate, MKCoordinateSpanMake(0.01, 0.01));
    [mapView setRegion:region animated:NO];
}

在您的MKMapViewDelegate中

，以便在找到用户的位置后将地图视图移动到该位置。

这将在地图视图中的地图视图中显示一个蓝点，就像地图应用程序一样。

iOS- MKMapKit - 如何在用户位置删除注释？

2 个答案: