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HowTo - Displaying Maps in a View with Swift 2.0

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In Swift 2.0, Apple has added MapKit, making it very easy for developers to incorporate the necessary map elements in a View.

Swift
import SwiftUI
import MapKit

struct MapView: View{
    // Set initial display area
    @State private var region: MKCoordinateRegion = MKCoordinateRegion(
        center: CLLocationCoordinate2D(latitude: 38.92083, longitude: 121.63917),
        span: MKCoordinateSpan(latitudeDelta: 0.5, longitudeDelta: 0.5)
    )
    
    // Set to continuously track user's current location
    @State private var trackmode = MapUserTrackingMode.follow
    
    // Set marker point information
    let dots: [MapDot] = [
        MapDot(title: "point1",
               coordinate: CLLocationCoordinate2D(latitude: 38.92083, longitude: 121.63917),
               color: .red),
        MapDot(title: "point2",
               coordinate: CLLocationCoordinate2D(latitude: 38.92183, longitude: 121.62717),
               color: .blue)
    ]
    
    @StateObject var store = Store()
    
    var body: some View {
        ZStack(alignment: .bottom){
            Map(coordinateRegion: $region,
                interactionModes: .all, // .pan, .zoom, .all
                showsUserLocation: true, // Show user's current location
                userTrackingMode: $trackmode, // Update user location
                annotationItems: dots // Marker point data
            ){ item in
                // Marker point display, can also use built-in MapPin, but MapPin can't respond to user input
                MapAnnotation(coordinate: item.coordinate){
                    // Uncertain if it's a bug, but currently Text cannot be displayed in iOS, can be displayed in macOS
                    Label(item.title, systemImage: "star.fill")
                        .font(.body)
                        .foregroundColor(item.color)
                        .onTapGesture {
                            print(item.title)
                        }
                }
            }
        }
        .edgesIgnoringSafeArea(.all)
    }
}

// Marker point data, must conform to Identifiable
struct MapDot: Identifiable{
    let id = UUID()
    let title: String
    let coordinate: CLLocationCoordinate2D
    let color: Color
}

class Store: ObservableObject {
    let manager = CLLocationManager()
    init() {
        // Request location access permission. Need to set Privacy - Location When In Use Usage Description in plist
        // If displaying current user location is not needed, then no need to request permission
        #if os(iOS)
            manager.requestWhenInUseAuthorization()
        #endif
    }
}

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Fatbobman(东坡肘子)

I'm passionate about life and sharing knowledge. My blog focuses on Swift, SwiftUI, Core Data, and Swift Data. Follow my social media for the latest updates.

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