MKMapView showAnnotations behavior

Question

My MKMapView is not fitting correctly the only two annotations I added to it.

There's not much I can think of why this is happening. I have another map in a different view controller and showAnnotations(_:animated) is working correctly. And by comparing their respective code I can't find anything that may cause that behavior.

The code is fundamentally this:

override func viewDidLoad() {
    super.viewDidLoad()
    annotationOrigin = aCoordinate
    annotationDest = bCoordinate
    mapView.addAnnotations([annotationOrigin, annotationDest], animated: true)   
}

func mapViewDidFinishRenderingMap(_ mapView: MKMapView, fullyRendered: Bool) {
    mapView.showAnnotations([annotationOrigin, annotationDest], animated: true)
}

Answer 1

You may try this

 func zoomToFitMapAnnotations(aMapView:MKMapView)
{
    if(aMapView.annotations.count == 0)
    {
          return
    }


    var topLeftCoord = CLLocationCoordinate2D.init(latitude: -90, longitude: 180)


    var bottomRightCoord = CLLocationCoordinate2D.init(latitude: 90, longitude: -180)


    for i in 0..<myMapView.annotations.count
    {
        let annotation = myMapView.annotations[i]

        topLeftCoord.longitude = fmin(topLeftCoord.longitude, annotation.coordinate.longitude);
        topLeftCoord.latitude = fmax(topLeftCoord.latitude, annotation.coordinate.latitude);

        bottomRightCoord.longitude = fmax(bottomRightCoord.longitude, annotation.coordinate.longitude);
        bottomRightCoord.latitude = fmin(bottomRightCoord.latitude, annotation.coordinate.latitude);
    }


    let resd = CLLocationCoordinate2D.init(latitude: topLeftCoord.latitude - (topLeftCoord.latitude - bottomRightCoord.latitude) * 0.5, longitude: topLeftCoord.longitude + (bottomRightCoord.longitude - topLeftCoord.longitude) * 0.5)

    let span = MKCoordinateSpan.init(latitudeDelta: fabs(topLeftCoord.latitude - bottomRightCoord.latitude) * 1.3, longitudeDelta: fabs(bottomRightCoord.longitude - topLeftCoord.longitude) * 1.3)

    var region = MKCoordinateRegion.init(center: resd, span: span);



    region = aMapView.regionThatFits(region)

    aMapView.setRegion(region, animated: true)


}