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  StackOverflow 文档
 
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  iOS 教程
 
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  MKMapView
 
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  使用注释
 
获取所有注释
//following method returns all annotations object added on map
NSArray *allAnnotations = mapView.annotations;
获取注释视图
for (id<MKAnnotation> annotation in mapView.annotations)
{
    MKAnnotationView* annotationView = [mapView viewForAnnotation:annotation];
    if (annotationView)
    {
       // Do something with annotation view 
       // for e.g change image of annotation view
       annotationView.image = [UIImage imageNamed:@"SelectedPin.png"];
    }
}
删除所有注释
[mapView removeAnnotations:mapView.annotations]
删除单个注释
//getting all Annotation
NSArray *allAnnotations = self.myMapView.annotations;
if (allAnnotations.count > 0)
{
    //getting first annoation
    id <MKAnnotation> annotation=[allAnnotations firstObject];
    
    //removing annotation
    [mapView removeAnnotation:annotation];
    
}