关于ios：如何在SwiftUI中获取MKMapView Directions

How to get MKMapView Directions in SwiftUI

在我的应用程序中，我正在使用 MKMapView SwiftUI 实现。我的地图运行良好，但我想在从 ContentView 中点击按钮时获取路线。我已经在下面更详细地解释了......

这是我的内容视图：

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struct ContentView: View {

var body: some View {
VStack {
AppleMapView(coordinate: CLLocationCoordinate2D(latitude: 40.7127, longitude: -74.0059))
.frame(height: 400)

Button(action: {
**// !!! I want to call AppleMapView/getDirections() method here !!!**
}) {
Text("Get Directions")
}
}
}
}

这是我的地图视图：

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struct AppleMapView: UIViewRepresentable {
var coordinate: CLLocationCoordinate2D

func makeUIView(context: Context) -> MKMapView {
// some codes //
}

func updateUIView(_ uiView: MKMapView, context: Context) {
// some codes //
}

func makeCoordinator() -> Coordinator {
return Coordinator()
}

func getDirections() {
// some codes //
}

class Coordinator: NSObject, MKMapViewDelegate {

func mapView(_ mapView: MKMapView, rendererFor overlay: MKOverlay) -> MKOverlayRenderer {
let renderer = MKPolylineRenderer(overlay: overlay)
renderer.strokeColor = .blue
renderer.lineWidth = 4
return renderer
}

}
}

谢谢。

相关讨论

在您的 MapView 上创建一个 @Binding 属性，然后在 Button 操作中从您的 ContentView 设置 directions。

这样你的 updateUIView 将被更新的值相应地调用。

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struct ContentView: View {
@State var directions: [CLLocation] = []

var body: some View {
VStack {
MapView(directions: $directions)

Button(action: {
// Directions are Nepal to India
self.directions = [CLLocation(latitude: 27.2041206, longitude: 84.6093928), CLLocation(latitude: 20.7712763, longitude: 73.7317739)]
}) {
Text("Get Directions")
}
}
}
}

struct MapView: UIViewRepresentable {
@Binding var directions: [CLLocation]

class Coordinator: NSObject, MKMapViewDelegate {
var parent: MapView

init(_ parent: MapView) {
self.parent = parent
}

func mapView(_ mapView: MKMapView, rendererFor overlay: MKOverlay) -> MKOverlayRenderer {
let renderer = MKPolylineRenderer(overlay: overlay)
renderer.strokeColor = .blue
renderer.lineWidth = 4
return renderer
}
}

func makeCoordinator() -> Coordinator {
Coordinator(self)
}

func makeUIView(context: Context) -> MKMapView {
return MKMapView()
}

func updateUIView(_ mapView: MKMapView, context: Context) {
var coordinates = self.directions.map({(location: CLLocation!) -> CLLocationCoordinate2D in return location.coordinate})
let polyline = MKPolyline(coordinates: &coordinates, count: self.directions.count)

mapView.delegate = context.coordinator
mapView.addOverlay(polyline)
}
}