Automatically refreshing view-based annotation coordinates

ViewController.swift

import UIKit
import MapboxMaps

class ViewController: UIViewController {
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        let mapView = MapView(frame: view.bounds)
        mapView.autoresizingMask = [.flexibleHeight, .flexibleWidth]
        view.addSubview(mapView)
        
        mapView.mapboxMap.onNext(.mapLoaded) { event in
            let annotationView = UIView(frame: CGRect(x: 0, y: 0, width: 35, height: 35))
            annotationView.backgroundColor = .red
            try! mapView.viewAnnotations.add(annotationView, options: self.annotationOptions)
            self.refresh(annotation: annotationView, in: mapView)
        }
    }
    
    var annotationOptions: ViewAnnotationOptions {
        // For demo purposes, we use a hardcoded coordinate.
        ViewAnnotationOptions(
            geometry: Geometry.point(Point(.init(latitude:39.50, longitude:-98.35))),
            allowOverlap: true,
            anchor: .center,
            selected: true
        )
    }
    
    func refresh(annotation: UIView, in mapView: MapView) {
        try! mapView.viewAnnotations.update(annotation, options: annotationOptions)
        
        // Continuously update the coordinates for demo purposes. This simulates
        // updates from an API response or from user location updates.
        DispatchQueue.main.asyncAfter(deadline: .now() + 1.5) {
            self.refresh(annotation: annotation, in: mapView)
        }
    }
}