在 SwiftUI 中点击 MKMapView [英] Tapping an MKMapView in SwiftUI

问题描述

我在 SwiftUI 应用中有一张地图.它正在发挥作用；但现在我希望能够点击它并知道点击的纬度和经度.这是当前的代码:

I have a map in a SwiftUI app. It is working up to a point; but now I want to be able to tap on it and know the latitude and longitude of the tap. Here is the current code:

import SwiftUI
import MapKit

struct MapView: UIViewRepresentable {
    @Binding var centerCoordinate: CLLocationCoordinate2D
    
    func makeUIView(context: Context) -> MKMapView {
        let mapView = MKMapView()
        mapView.delegate = context.coordinator
        
        let gRecognizer = UITapGestureRecognizer(target: context.coordinator,
                                action: #selector(Coordinator.tapHandler(_:)))
        mapView.addGestureRecognizer(gRecognizer)
        return mapView
    }

    func updateUIView(_ view: MKMapView, context: Context) {
        //print(#function)
    }

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

    class Coordinator: NSObject, MKMapViewDelegate {
        var parent: MapView

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

        let gRecognizer = UITapGestureRecognizer(target: self,
                                                 action: #selector(tapHandler(_:)))
        
        @objc func tapHandler(_ gesture: UITapGestureRecognizer) {
            print(#function)
            .... get useful information here ...
        }
    }
}

在这种状态下，我可以看到我何时点击，但我没有得到我需要的信息(即点击坐标).在网上搜索后，我尝试了一些代码的变体.在这一点上，它还没有工作.非常欢迎任何相关的提示.

In this state I can see when I tap, but I don't get the information I need (.i.e coordinates of the tap). I have tried a few variations of the code after searching the net. At this point it is not yet working. Any relevant tip on the way to go would be very welcome.

推荐答案

我也遇到过类似的情况，这就是我所做的.我制作了 Coordinator UIGestureRecognizerDelegate，并确保设置了 gRecognizer 委托，并将其添加到地图中.类似的东西:

I had a similar situation, and this is what I did. I made Coordinator UIGestureRecognizerDelegate, and ensure gRecognizer delegate is set to it, and add it to the map. Something like:

struct MapView: UIViewRepresentable {
@Binding var centerCoordinate: CLLocationCoordinate2D

let mapView = MKMapView()

func makeUIView(context: Context) -> MKMapView {
    mapView.delegate = context.coordinator
    return mapView
}

func updateUIView(_ view: MKMapView, context: Context) {
    //print(#function)
}

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

class Coordinator: NSObject, MKMapViewDelegate, UIGestureRecognizerDelegate {
    var parent: MapView

    var gRecognizer = UITapGestureRecognizer()

    init(_ parent: MapView) {
        self.parent = parent
        super.init()
        self.gRecognizer = UITapGestureRecognizer(target: self, action: #selector(tapHandler)) 
        self.gRecognizer.delegate = self
        self.parent.mapView.addGestureRecognizer(gRecognizer)
    }

    @objc func tapHandler(_ gesture: UITapGestureRecognizer) {
        // position on the screen, CGPoint
        let location = gRecognizer.location(in: self.parent.mapView)
        // position on the map, CLLocationCoordinate2D
        let coordinate = self.parent.mapView.convert(location, toCoordinateFrom: self.parent.mapView)
        
    }
}
}

这篇关于在 SwiftUI 中点击 MKMapView的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！