How to change displayPriority of MKUserLocation annotation in MapView?

Question

I have a MapView displaying some annotations with displayPriority = .defaultHight to allow automatic clustering.

The MapView also displays the current user location which has a default display priority of required.

This causes my annotations to be hidden by the user location annotation when they are very close together.

I want to change this behavior by setting the display priority of the user location annotation to defaultLow.

I tried using this approach:

func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? {
    if annotation is MKUserLocation {
        let userView = mapView.view(for: annotation)
        userView?.displayPriority = .defaultLow
        return userView
    }
    return mapView.view(for: annotation)
}

However userView is always nil and therefore my displayPriority modification is not applied.

Any ideas how the displayPriority of the MKUserLocation annotation view can be changed?

Did you find an answer/workaround to your problem yet? – ChaosCoder Nov 04 '19 at 21:27 — ChaosCoder, Nov 04 '19 at 21:27
Not yet unfortunately. – funkenstrahlen Nov 15 '19 at 10:30 — funkenstrahlen, Nov 15 '19 at 10:30

score 1 · Answer 1 · answered Apr 26 '20 at 05:37

I spent hours trying to solve this problem by customizing the default user location annotation, but to no avail.

Instead, as a workaround, I made my own location marker and hid the default location annotation. Here's my code:

Add an annotaion variable to your viewController:

private var userLocation: MKPointAnnotation?

In your viewDidLoad, hide the default location marker:

mapView.showsUserLocation = false

Update the location in didUpdateLocations:

func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
        guard let userLocation = locations.first else { return }
        if self.userLocation == nil {
            let location = MKPointAnnotation()
            location.title = "My Location"
            location.coordinate = userLocation.coordinate
            mapView.addAnnotation(location)
            self.userLocation = location
        } else {
            self.userLocation?.coordinate = userLocation.coordinate
        }
    }

Then customize the annotation view in viewFor annotation:

func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? {
            // user location annotation
            let identifier = "userLocation"
            var annotationView = mapView.dequeueReusableAnnotationView(withIdentifier: identifier)

            if annotationView == nil {
                annotationView = MKMarkerAnnotationView(annotation: annotation, reuseIdentifier: identifier)
                (annotationView as? MKMarkerAnnotationView)?.markerTintColor = .blue
                annotationView?.canShowCallout = true
            } else {
                annotationView?.annotation = annotation
            }
            annotationView?.displayPriority = .defaultLow
            return annotationView
}

I changed the annotation's displayPriority to .defaultLow to make sure it won't hide other annotations.

Let me know if this helps!

score 0 · Answer 2 · answered Dec 22 '22 at 02:55

In case anyone is still struggling with this, you can do this using func mapView(_ mapView: MKMapView, didAdd views: [MKAnnotationView]):

// MARK: - MKMapViewDelegate

func mapView(_ mapView: MKMapView, didAdd views: [MKAnnotationView]) {
    for view in views {
        if view.annotation is MKUserLocation {
            view.displayPriority = .defaultLow
            break
        }
    }
}

This way you can still use the system provided view for MKUserLocation without having to construct your own manually.

How to change displayPriority of MKUserLocation annotation in MapView?

2 Answers2