How to animate moving of MKOverlay on MKMapView Swift

Question

I am working on a map application in which i have to animate movement of an aeroplane, based on user location

So i implemented a custom class MKPlaneAndArrow by subclassing MKOverlay

class MKPlaneAndArrow : NSObject, MKOverlay {

  //@objc dynamic var coordinate: CLLocationCoordinate2D
  //the above method also does not change location

  //to change the coordinate after initialization
  var coordinate: CLLocationCoordinate2D {
    willSet {
      willChangeValue(forKey: #keyPath(coordinate))
    }
    didSet {
      didChangeValue(forKey: #keyPath(coordinate))
    }
  }

  var boundingMapRect: MKMapRect

  init( center: CLLocationCoordinate2D, boundingMapRect_: MKMapRect) {

    self.coordinate = center
    self.boundingMapRect = boundingMapRect_

  }

}

Now, when location delegate didUpdateLocations is called, i want to change the coordinate of MKPlaneAndArrow overlay to the current location coordinate so i wrote the following inside didUpdateLocations

    //if not already added annotation
if !HomeVC.flagAlreadyAddedPlaneAnnotation {

    let planeAndArrow = MKPlaneAndArrow.init(center: lastUserLocation.coordinate, boundingMapRect_: mapRect)
    mapView.add(planeAndArrow)
    //Did updateLocations will not add the annotation again
    HomeVC.flagAlreadyAddedPlaneAnnotation = true

}
//get last user location
guard let lastUserLocation:CLLocation = locations.last  else {
    print("no location")
    return
}
 //change coordinate of `MKPlaneAndArrow` overlay
for overlay in mapView.overlays {

    if let myPlane = overlay as? MKPlaneAndArrow {
     myPlane.coordinate = lastUserLocation.coordinate 
    }
}

I have setup breakpoints and they hit the line myPlane.coordinate = ... But i don't know why on earth the coordinate change is not visible on map

Animating

If the above code changes the coordinate, it will not animate the change. I also want it to animate. Like movement of user location on Google Maps or apple maps

I was successfully able to change the coordinate of MKAnnotation with animation. But with overlay, i have been searching for hours but could not find a solution

I saw the following questions on SO along with many others

Notes:

Can't Use MkAnnotation because these stay the same size if you zoom, while overlay sizes are relative to the zoom scale
If you need my MKOverlayRenderer class, just ask in the comments. My renderer is just drawing an image using `context.draw

Thanks in advance

The problem is that the only thing you can animate is a view (or layer), and you don't have one of those. — matt
Thanks. So @matt. what will be the best way to handle this problem? — Awais Fayyaz
Well, I really don't think your airplane was ever appropriate as an overlay to begin with. An overlay is a drawing delineating some region of the surface of the earth. An annotation is a drawing associated with a coordinate. I think you'd be happier with an annotation whose drawing size changes together with the zoom of the map, as discussed here for example: stackoverflow.com/questions/8286711/… — matt

ingconti ingconti · Accepted Answer · 2020-03-20T10:44:38

I resorted in calculating "UIKit" coords from CLLocationsCoords, adding a std UIImageView so I move animate.. poor solution but very efficient. :(

How to animate moving of MKOverlay on MKMapView Swift

Animating

1 Answers