SwiftUI封装Google地图时GMSMarker点击跳转及delegate设置问题

• 不能直接将GMSMapView.delegate设置为GoogleMapView本身：GoogleMapView是值类型结构体，不满足代理要求的类类型约束
• 必须使用UIViewRepresentable配套的Coordinator协调器作为代理实现载体，这是SwiftUI桥接UIKit控件时处理代理事件的标准方案
• 你原有代码中mapView.delegate = ViewController()的写法是无效的，临时创建的ViewController实例在方法执行完就会被释放，代理回调完全无法触发

import SwiftUI
import GoogleMaps

struct GoogleMapView: UIViewRepresentable {
    // 点击Marker的回调闭包，用于向SwiftUI层传递事件
    var onMarkerTapped: (GMSMarker) -> Void
    
    func makeCoordinator() -> Coordinator {
        Coordinator(parent: self)
    }
    
    func updateUIView(_ uiView: GMSMapView, context: Context) {
        let marker = GMSMarker()
        marker.position = CLLocationCoordinate2D(latitude: 20, longitude: 50)
        marker.map = uiView
    }

    func makeUIView(context: Context) -> GMSMapView {
        let camera = GMSCameraPosition.camera(withLatitude: 20, longitude: 50, zoom: 10)
        let mapView = GMSMapView(frame: .zero, camera: camera)
        // 核心：将delegate设置为上下文中的协调器实例
        mapView.delegate = context.coordinator
        return mapView
    }
    
    // 内部协调器类，实现GMSMapViewDelegate协议
    class Coordinator: NSObject, GMSMapViewDelegate {
        var parent: GoogleMapView
        
        init(parent: GoogleMapView) {
            self.parent = parent
        }
        
        // 实现Marker点击的代理回调
        func mapView(_ mapView: GMSMapView, didTap marker: GMSMarker) -> Bool {
            parent.onMarkerTapped(marker)
            // 返回true表示已自定义处理事件，不需要触发地图默认点击行为
            return true
        }
    }
}

struct ContentView: View {
    @State private var isShowDetail = false
    @State private var tappedMarker: GMSMarker?
    
    var body: some View {
        NavigationStack {
            GoogleMapView { marker in
                // 收到Marker点击事件，触发跳转
                tappedMarker = marker
                isShowDetail = true
            }
            .ignoresSafeArea()
            // 用sheet/push都可以实现跳转，这里以sheet为例
            .sheet(isPresented: $isShowDetail) {
                MarkerDetailView(marker: $tappedMarker)
            }
        }
    }
}

// 示例跳转目标视图
struct MarkerDetailView: View {
    @Binding var marker: GMSMarker?
    
    var body: some View {
        VStack(spacing: 20) {
            Text("你点击了Marker")
            Text("坐标：\(marker?.position.latitude ?? 0), \(marker?.position.longitude ?? 0)")
        }
        .padding()
    }
}

内容的提问来源于stack exchange，提问作者Santanu