MKAnnotationView custom callout is invisible to Accessibility (VoiceOver)

Question

I have a MKAnnotationView subclass and place several of them on an MKMapView. The MKAnnotationView subclass sets some accessibility elements like this:

func applyAccessibility() {
    
    self.isAccessibilityElement = true
    self.accessibilityTraits = [.none]
    
    self.accessibilityLabel = "Bus stop map pin"
    self.accessibilityValue = busStop.name
}

VoiceOver reads out the names of the bus stops that are pinned on the map.

I then use a UIView subclass as the callout view when a bus stop is tapped.

func mapView(_ mapView: MKMapView, didSelect view: MKAnnotationView) {
    
    if let annotation = view.annotation
    {
        if annotation is MKUserLocation
        {
            // This is our location marker
            return
        }
        
        busStopAnnotationCalloutView.setupForAnnotationView(view, delegate: self)
        
        view.addSubview(busStopAnnotationCalloutView)
        
        mapView.setCenter(annotation.coordinate, animated: true)
    }
}

This works great, however this callout view is totally invisible to VoiceOver.

In the init of the callout view I set:

isAccessibilityElement = true
accessibilityTraits = .none
accessibilityLabel = "Callout view"
accessibilityIdentifier = "BusStopAnnotationCalloutView.callout"

and it also creates it's own labels and a button of which I set similar like this:

label.isAccessibilityElement = true
label.accessibilityTraits = .header
label.accessibilityLabel = "\(busStop.name)"

UIButton

button.isAccessibilityElement = true
button.accessibilityTraits = .button
button.accessibilityLabel = "Select this bus stop"

but none of these elements are visible to VoiceOver. The Accessibility Inspector can't see them.

As I move around the view with the Accessibility Inspector it just picks up and MKAnnotation's that are on the map underneath the callout.

EDIT --------

I have created a small example project that has a custom callout view that just won't get any accessibility.

Example project

And there's also a short screen recording showing the problem:

on YouTube

Divaricate

I Can't download your example but I can reproduce the problem with my project. Did you try to use an UIAccessibilityContainer? #26538859 (Still on my todo list, sorry) – Polydactyl

No, that question doesn't really explain it, but i'll do some research on that. – Divaricate

Answer 1

The issue here is that your callout view is a child of your annotation view. Therefore if your annotation view has it's isAccessibilityElement set to true you can not focus on the callout. A way of solving this is setting the isAccessibilityElement of your annotation to false each time it is selected and vice versa.

Obstetric

Wow! You are correct. Even Apple didn't pick up on this through both DTS and Bug Report. Thank you. – Divaricate

Answer 2

After going directly to Apple with a Developer Technical Support request, they suggested it is a bug, however as this doesn't work on any version of iOS that I tested, i'd suggest it is more an oversight than a bug and i'm surprised no-one else has wanted to make a map view callout accessible.

Apple DTS also asked if I wanted them to look for a workaround and after a few days they came back to say there simply isn't one!

So for now, as of iOS 12.4, the answer here is that it's just not possible.

Divaricate