swift地图定位（十四）使用 MKAnnotationView自定义大头针视图

import UIKit
import MapKit

class ViewController: UIViewController {

    @IBOutlet weak var mapView: MKMapView!
    
    lazy var geoCoder: CLGeocoder = {
        return CLGeocoder()
    }()
    
    override func viewDidLoad() {
        super.viewDidLoad()
        mapView.delegate = self
    }
    
    override func touchesBegan(_ touches: Set, with event: UIEvent?){
        let point = touches.first?.location(in: mapView)
        let coordinate = mapView.convert(point!, toCoordinateFrom: mapView)
        let annotation = addAnnotation(coordinate, title: "title", subTitle: "subTitle")
        let location = CLLocation(latitude: coordinate.latitude, longitude: coordinate.longitude)
        geoCoder.reverseGeocodeLocation(location) { (pls: [CLPlacemark]?, error: Error?) -> Void in
            if error == nil {
                let pl = pls?.first
                print(pl)//Optional(祖冲之路705号, 中国上海市浦东新区张江镇祖冲之路705号 @ <+31.20264860,+121.59036900> +/- 100.00m, region CLCircularRegion (identifier:'<+31.20264850,+121.59036900> radius 49.30', center:<+31.20264850,+121.59036900>, radius:49.30m))
                annotation.title = pl?.locality
                annotation.subtitle = pl?.name
            }
        }
    }
    
    func addAnnotation(_ coordinate: CLLocationCoordinate2D, title: String, subTitle: String) -> TGAnnotation {
        let annotation: TGAnnotation = TGAnnotation()
        annotation.coordinate = coordinate
        annotation.title = title
        annotation.subtitle = subTitle
        mapView.addAnnotation(annotation)
        return annotation
    }
}

class TGAnnotation: NSObject, MKAnnotation {
    var coordinate: CLLocationCoordinate2D = CLLocationCoordinate2DMake(0, 0)
    var title: String?
    var subtitle: String?
}

extension ViewController: MKMapViewDelegate {
    func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? {
        // 使用 MKAnnotationView自定义大头针
        let identifier = "item"
        var annotationView = mapView.dequeueReusableAnnotationView(withIdentifier: identifier)
        if annotationView == nil {
            annotationView = MKAnnotationView(annotation: annotation, reuseIdentifier: identifier)
        }
        annotationView?.annotation = annotation// 重要
        annotationView?.image = UIImage(named: "category_1")// 设置打头针的图片
        annotationView?.centerOffset = CGPoint(x: 0, y: 0)// 设置大头针中心偏移量
        annotationView?.canShowCallout = true// 设置弹框
        annotationView?.calloutOffset = CGPoint(x: 10, y: 0)// 设置弹框的偏移量
        
        let leftIV = UIImageView(frame: CGRect(x: 0, y: 0, width: 38, height: 44))
        let leftImage = UIImage(named: "category_2")
        leftIV.image = leftImage
        annotationView?.leftCalloutAccessoryView = leftIV// 设置弹框的左侧视图
        
        let rightIV = UIImageView(frame: CGRect(x: 0, y: 0, width: 38, height: 44))
        let rightImage = UIImage(named: "category_3")
        rightIV.image = rightImage
        annotationView?.rightCalloutAccessoryView = rightIV// 设置弹框的右侧视图
        
        if #available(iOS 9.0, *) {
//            let detailIV = UIImageView(frame: CGRect(x: 0, y: 0, width: 38, height: 44))
//            let detailImage = UIImage(named: "category_4")
//            detailIV.image = detailImage
//            annotationView?.detailCalloutAccessoryView = detailIV// 设置下部视图
        }
        annotationView?.isDraggable = true// 设置大头针可以拖动
        return annotationView
    }
}