添加地图注释

Question

我一直在试图让地图上显示多个地图，但它不起作用。谁能帮我吗？我正在使用下面的代码：

- (void)viewDidLoad 

    { 
// Set some coordinates for our position (Buckingham Palace!) 
CLLocationCoordinate2D location; 
location.latitude = (double) 51.501468; 
location.longitude = (double) -0.141596; 

// Add the annotation to our map view 
MapViewAnnotation *newAnnotation = [[MapViewAnnotation alloc] initWithTitle:@"Buckingham Palace" andCoordinate:location]; 
[self.mapView addAnnotation:newAnnotation]; 


} 


- (void)mapView:(MKMapView *)mv didAddAnnotationViews:(NSArray *)views 
{ 
MKAnnotationView *annotationView = [views objectAtIndex:0]; 
id <MKAnnotation> mp = [annotationView annotation]; 
MKCoordinateRegion region = MKCoordinateRegionMakeWithDistance([mp coordinate], 1500, 1500); 
[mv setRegion:region animated:YES]; 
[mv selectAnnotation:mp animated:YES]; 
} 

Answer 1

您是否设置了mapview委托？

self.mapView.delegate = self;