ios - iOS- MKMapKit-我如何在用户位置上添加注释？

Question

我的应用程序上有用户位置，但是如何在当前用户位置上放置注释？我是否必须获取用户位置的经纬度并以这种方式删除注释？或者我该怎么做？

Answer 1

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

3. 设置它的.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
   

4. 设置它的.m：

   #import "Annotation.h"
   
   @implementation Annotation
   @synthesize coordinate, title, subtitle;
   
   @end
   

   1. 设置viewDidLoad

         if ([CLLocationManager locationServicesEnabled]) {
      
         locationManager = [[CLLocationManager alloc] init];
      
         [locationManager setDelegate:self];
      
         [locationManager setDesiredAccuracy: kCLLocationAccuracyBestForNavigation];
      
         [locationManager startUpdatingLocation];
      
         }
      
        self.mapView.delegate = self; 
      

   2. 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

最简单的方法是设置showsUserLocation为YES您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MKMapViewDelegate找到用户的位置后，让地图视图移动到该位置。

这将在用户位置的地图视图上显示一个蓝点，就像地图应用程序一样。