MKMapView visible region padding

Question

Dera colleagues,

I'm struggle to implement visible region with native MKMapView. I need to have an exactly the same feature as Google Map SDK Visible Region.

Basically it means to have a sort of padding in the bottom to following code:

let span = MKCoordinateSpan(latitudeDelta: 0.8, longitudeDelta: 0.8)
let reg = MKCoordinateRegion(center: someMyCoordinate, span: span)
mapView.setRegion(reg, animated: true)

It needs to be like this: once I've add some padding in UIView coordinates, it should shift Map center and adjust zoom to make Coordinate Region fully visible, take into account the padding.

Probably my description Is a bit messy, but if you take a look on this video it becomes absolutely clear.

Thank you in advance!

Answer 1

Thanks to approach suggested above, complete solution is following.

import Foundation
import MapKit
extension MKCoordinateRegion{
    var mapRect:MKMapRect {
        get{
            let a = MKMapPointForCoordinate(CLLocationCoordinate2DMake(
                   self.center.latitude + self.span.latitudeDelta / 2,
                   self.center.longitude - self.span.longitudeDelta / 2))

            let b = MKMapPointForCoordinate(CLLocationCoordinate2DMake(
                    self.center.latitude - self.span.latitudeDelta / 2,
                    self.center.longitude + self.span.longitudeDelta / 2))

            return MKMapRectMake(min(a.x,b.x), min(a.y,b.y), abs(a.x-b.x), abs(a.y-b.y))
        }
    }
}

extension MKMapView {
    func setVisibleRegion(mapRegion: MKCoordinateRegion, edgePadding insets: UIEdgeInsets, animated animate: Bool) {
        self.setVisibleMapRect(mapRegion.mapRect, edgePadding: insets , animated: animate)
    }
}

Now you can just use setVisibleRegion func.

Answer 2

If you need a padding from the bottom of 100 in swift you could simply write:

mapView.layoutMargins = UIEdgeInsets(top: 10, right: 10, bottom: 100, left: 10)

Then you can check this centering the map on some annotations like this:

mapView.showAnnotations(mapView.annotations, animated: true)

Answer 3

If you print your visible region you will see that the span will be padded since it needs to fit the view. The center coordinate will still be in the center of the view. I'm not sure what you want to do but I guess it can be archived with

setVisibleMapRect:edgePadding:animated:

You need to have the region converted to a MKMapRect. See Convert MKCoordinateRegion to MKMapRect on how to do that