SwiftUI Tutorial (Combining Views) - Map Pin missing

Question

Working through the "Combining Views" (first) tutorial on SwiftUI, I notice that the images and previews in the tutorial show a pin on the map for the specified location. My app doesn't have that.

I double checked the code in the download and I can't see any difference... except that my lat/long are specified as (latitude: 34.011286, longitude: -116.166868) and the download code has (latitude: 34.011_286, longitude: -116.166_868)...

Is this just a tutoirial glitch? (That the pin doesn't appear...)

Or a documentation error? (It isn't supposed to appear...)

Given that it looks useful, how difficult would it be to add the pin?

Thanks in advance...

Swift

1.1k

Posted by

GilW

Reply

Add a Comment

Answer 1

//
// MapView.swift
// Landmark
//
// Created by Abenx on 2020/6/26.
//

import SwiftUI
import MapKit

#if !os(macOS)
struct MapView: UIViewRepresentable {
  var coordinate: CLLocationCoordinate2D

  func makeUIView(context: Context) -> MKMapView {
    MKMapView(frame: .zero)
  }

  func updateUIView( uiView: MKMapView, context: Context) {
    self.updateView(uiView, context: context)
  }
}
#else
struct MapView: NSViewRepresentable {
  var coordinate: CLLocationCoordinate2D

  func makeNSView(context: Context) -> MKMapView {
    MKMapView(frame: .zero)
  }

  func updateNSView( nsView: MKMapView, context: Context) {
    self.updateView(nsView, context: context)
  }
}
#endif

extension MapView {
  func updateView( uiView: MKMapView, context: Context) {
    let span = MKCoordinateSpan(latitudeDelta: 0.01, longitudeDelta: 0.01)
    let region = MKCoordinateRegion(center: coordinate, span: span)
    let annotation = MKPointAnnotation()
    annotation.coordinate = coordinate

    uiView.setRegion(region, animated: true)
    uiView.addAnnotation(annotation)
  }
}


struct MapViewPreviews: PreviewProvider {
  static var previews: some View {
    MapView(coordinate: CLLocationCoordinate2D(
          latitude: 39.910358, longitude: 116.469841))
  }
}

Posted by

Abenx

Add a Comment

SwiftUI Tutorial (Combining Views) - Map Pin missing

Replies