Marker hinzufügen (iOS)

import UIKit
import MapLibre

class MarkerViewController: UIViewController, MLNMapViewDelegate {
    private var mapView: MLNMapView!

    override func viewDidLoad() {
        super.viewDidLoad()

        let styleURL = URL(string:
            "https://tiles.smartmaps.cloud/styles/v1/smartmaps/light/style.json?apiKey=[INSERT API-KEY]&channel=app"
        )!

        mapView = MLNMapView(frame: view.bounds, styleURL: styleURL)
        mapView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
        mapView.delegate = self
        mapView.setCenter(
            CLLocationCoordinate2D(latitude: 49.0069, longitude: 8.4037),
            zoomLevel: 12,
            animated: false
        )
        view.addSubview(mapView)
    }

    func mapView(_ mapView: MLNMapView, didFinishLoading style: MLNStyle) {
        let annotation = MLNPointAnnotation()
        annotation.coordinate = CLLocationCoordinate2D(
            latitude: 49.0069,
            longitude: 8.4037
        )
        annotation.title = "Karlsruhe"
        annotation.subtitle = "SmartMaps Headquarters"
        mapView.addAnnotation(annotation)
    }

    // Enable callout on tap
    func mapView(_ mapView: MLNMapView, annotationCanShowCallout annotation: MLNAnnotation) -> Bool {
        return true
    }
}

func mapView(_ mapView: MLNMapView, didFinishLoading style: MLNStyle) {
    let locations: [(CLLocationCoordinate2D, String, String)] = [
        (CLLocationCoordinate2D(latitude: 49.0069, longitude: 8.4037), "Karlsruhe", "Baden-Wuerttemberg"),
        (CLLocationCoordinate2D(latitude: 48.7758, longitude: 9.1829), "Stuttgart", "State Capital"),
        (CLLocationCoordinate2D(latitude: 49.4875, longitude: 8.4660), "Mannheim", "Rhine-Neckar Region"),
        (CLLocationCoordinate2D(latitude: 48.3705, longitude: 10.8978), "Augsburg", "Bavaria")
    ]

    var annotations = [MLNPointAnnotation]()
    for (coordinate, title, subtitle) in locations {
        let annotation = MLNPointAnnotation()
        annotation.coordinate = coordinate
        annotation.title = title
        annotation.subtitle = subtitle
        annotations.append(annotation)
    }

    mapView.addAnnotations(annotations)

    // Fit camera to show all annotations
    mapView.showAnnotations(annotations, animated: true)
}

func mapView(_ mapView: MLNMapView, imageFor annotation: MLNAnnotation) -> MLNAnnotationImage? {
    let reuseIdentifier = "custom-marker"

    if let existingImage = mapView.dequeueReusableAnnotationImage(withIdentifier: reuseIdentifier) {
        return existingImage
    }

    guard let image = UIImage(named: "custom-marker") else { return nil }

    return MLNAnnotationImage(image: image, reuseIdentifier: reuseIdentifier)
}