如何在此处执行地图标记单击(Ios swift)

class MapViewController: UIViewController, MKMapViewDelegate {
    // ...
    override func viewDidLoad() {
        super.viewDidLoad()
        mapView.delegate = self
    }
    // ...
}

let mapView = MKMapView(frame: CGRect(x: 0, y: 0, width: view.frame.width, height: view.frame.height))
view.addSubview(mapView)

func mapView(_ mapView: MKMapView, didSelect view: MKAnnotationView) {
    // 在这里执行地图标记单击的操作
    if let annotation = view.annotation as? MKPointAnnotation {
        // 获取标记的坐标
        let coordinate = annotation.coordinate
        // 执行你的操作，例如显示弹出窗口
        let alert = UIAlertController(title: "标记被点击", message: "坐标：\(coordinate.latitude), \(coordinate.longitude)", preferredStyle: .alert)
        alert.addAction(UIAlertAction(title: "确定", style: .default, handler: nil))
        present(alert, animated: true, completion: nil)
    }
}