[SwiftUI] Subscribe PassthroughSubject in UIViewRepresentable

AppleMapView.swift

import Combine
import MapKit
import SwiftUI

struct AppleMapView_Previews: PreviewProvider {
  static var previews: some View {
    AppleMapView()
  }
}

struct AppleMapView: UIViewRepresentable {
  @EnvironmentObject var mapViewEnvironment: MapViewEnvironment

  func makeUIView(context: Context) -> MKMapView {
    let view = MKMapView()
    view.mapType = .standard

    willAppear(context)

    return view
  }

  func updateUIView(_ uiView: MKMapView, context: UIViewRepresentableContext<AppleMapView>) {}

  static func dismantleUIView(_ uiView: MKMapView, coordinator: AppleMapView.Coordinator) {
    print("apple dismantleUIView")
    coordinator.cancellable.removeAll()
  }

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

  final class Coordinator {
    var cancellable = Set<AnyCancellable>()
  }
}

extension AppleMapView: MapViewProtocol {
  func willAppear(_ context: Context) {
    mapViewEnvironment.$value1
      .filter { $0 == "aaa" }
      .sink {
        print("=============== apple 1111 \($0)")
        self.aaa()
      }.store(in: &context.coordinator.cancellable)

    mapViewEnvironment.$value1
      .filter { $0 == "bbb" }
      .sink {
        print("=============== apple 1111 \($0)")
        self.bbb()
      }.store(in: &context.coordinator.cancellable)

    mapViewEnvironment.value2
      .filter { $0 == "aaa" }
      .sink {
        print("--------------- apple 2222 \($0)")
        self.aaa()
      }.store(in: &context.coordinator.cancellable)

    mapViewEnvironment.value2
      .filter { $0 == "bbb" }
      .sink {
        print("--------------- apple 2222 \($0)")
        self.bbb()
      }.store(in: &context.coordinator.cancellable)
  }

  func aaa() {
    print("AppleMapView - aaa")
  }

  func bbb() {
    print("AppleMapView - bbb")
  }
}

GoogleMapView.swift

import Combine
import GoogleMaps
import SwiftUI

struct GoogleMapView_Previews: PreviewProvider {
  static var previews: some View {
    GoogleMapView()
  }
}

struct GoogleMapView: UIViewRepresentable {
  @EnvironmentObject var mapViewEnvironment: MapViewEnvironment

  func makeUIView(context: Context) -> GMSMapView {
    let view = GMSMapView()
    view.mapType = .hybrid

    willAppear(context)

    return view
  }

  func updateUIView(_ uiView: GMSMapView, context: UIViewRepresentableContext<GoogleMapView>) {}

  static func dismantleUIView(_ uiView: GMSMapView, coordinator: GoogleMapView.Coordinator) {
    print("google dismantleUIView")
    coordinator.cancellable.removeAll()
  }

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

  final class Coordinator {
    var cancellable = Set<AnyCancellable>()
  }
}

extension GoogleMapView: MapViewProtocol {
  func willAppear(_ context: Context) {
    mapViewEnvironment.$value1
      .filter { $0 == "aaa" }
      .sink {
        print("============ google 1111 \($0)")
        self.aaa()
      }
      .store(in: &context.coordinator.cancellable)

    mapViewEnvironment.$value1
      .filter { $0 == "bbb" }
      .sink {
        print("============ google 1111 \($0)")
        self.bbb()
      }
      .store(in: &context.coordinator.cancellable)

    mapViewEnvironment.value2
      .filter { $0 == "aaa" }
      .sink {
        print("------------ google 2222 \($0)")
        self.aaa()
      }
      .store(in: &context.coordinator.cancellable)

    mapViewEnvironment.value2
      .filter { $0 == "bbb" }
      .sink {
        print("------------ google 2222 \($0)")
        self.bbb()
      }
      .store(in: &context.coordinator.cancellable)
  }

  func aaa() {
    print("GoogleMapView - aaa")
  }

  func bbb() {
    print("GoogleMapView - bbb")
  }
}

MapViewEnvironment.swift

import Combine
import SwiftUI

class MapViewEnvironment: ObservableObject {
  @Published var value1 = "aaa"
  var value2 = PassthroughSubject<String, Never>()
  @Published var currentMapCompany = "apple"
}

MapViewProtocol.swift

import SwiftUI

protocol MapViewProtocol {
  func aaa()
  func bbb()
}