有时候，当点击右侧标注按钮时，我的纬度和经度会出错

Question

每当我通过右侧标注附件按钮点击注释视图时，我获得该点的纬度和经度，工作正常，但有时候显示另一个针脚纬度和经度。

为什么会这样？

MKAnnotationView GetViewForAnnotation (MKMapView mapView, NSObject annotation)
 {

                    if (annotation is MKUserLocation)

                        return null;

                    // handle our two custom annotations

                    if (imgHazardType==1) 
                    {

                        const string PoliceAnnotationIdentifier = "PoliceAnnotationIdentifier";

                        MKAnnotationView pinView = (MKAnnotationView)mapView.DequeueReusableAnnotation (PoliceAnnotationIdentifier);

                        if (pinView == null) 
                        {

                            MKAnnotationView policeannotationView = new MKAnnotationView (annotation, PoliceAnnotationIdentifier);

                            policeannotationView.CanShowCallout = true;

                            UIImage flagImage = UIImage.FromFile ("Images/cop-point.png");

                            UIButton infobutton =UIButton.FromType(UIButtonType.DetailDisclosure);

                            policeannotationView.RightCalloutAccessoryView= infobutton;

                            infobutton.TouchUpInside+= (sender, e) => 
                            {

                                    NSUserDefaults.StandardUserDefaults.SetString((annotation as Annotation).Coordinate.Latitude.ToString (),"lat");
                                    NSUserDefaults.StandardUserDefaults.SetString((annotation as Annotation).Coordinate.Longitude.ToString (),"lon");


                            } ;


                            RectangleF resizeRect;
                            resizeRect.Size = flagImage.Size;

                            SizeF maxSize = View.Bounds.Inset (AnnotationPadding, AnnotationPadding).Size;

                            maxSize.Height -= NavigationController.NavigationBar.Frame.Size.Height - CalloutHeight;

                            if (resizeRect.Size.Width > maxSize.Width)

                                resizeRect.Size = new SizeF (maxSize.Width, resizeRect.Size.Height / resizeRect.Size.Width * maxSize.Width);

                            if (resizeRect.Size.Height > maxSize.Height)

                                resizeRect.Size = new SizeF (resizeRect.Size.Width / resizeRect.Size.Height * maxSize.Height, maxSize.Height);

                            resizeRect.Location = PointF.Empty;
                            UIGraphics.BeginImageContext (resizeRect.Size);
                            flagImage.Draw (resizeRect);

                            UIImage resizedImage = UIGraphics.GetImageFromCurrentImageContext ();
                            UIGraphics.EndImageContext ();
                            policeannotationView.Image = resizedImage;
                            policeannotationView.Opaque = false;
                            pinViews.Add (policeannotationView);

                            return policeannotationView;

                        }  
                        else 
                        {

                            pinView.Annotation = annotation;

                        }

                        return pinView;

                    } 

            return null;
        }