如何将 swiftUI 视图包装到 UIViewControllerRepresentable 中，以便 Google 地图相机在启动时聚焦于用户的位置？

Question

我目前正在尝试显示 Google 地图的实例，该实例在启动时使用 SwiftUI 关注用户位置。

为了显示地图，我在主视图文件中调用了 GoogMapView() 视图。它只是将相机设置为聚焦波士顿，并在启动时在波士顿上放置一个标记。

此处 GoogMapView.swift 的代码：

import SwiftUI
//import MapKit
import UIKit
import GoogleMaps
import GooglePlaces
import CoreLocation
import Foundation
    
struct GoogMapView : UIViewRepresentable {

//    private let locationManager = CLLocationManager()

    let marker : GMSMarker = GMSMarker()

    //Creates a `UIView` instance to be presented.
    func makeUIView(context: Context) -> GMSMapView {
        // Create a GMSCameraPosition
        let camera = GMSCameraPosition.camera(withLatitude: 42.361145, longitude: -71.057083, zoom: 16.0)
        let mapView = GMSMapView.map(withFrame: CGRect.zero, camera: camera)
        mapView.setMinZoom(14, maxZoom: 20)
        mapView.settings.compassButton = true
        mapView.isMyLocationEnabled = true
        mapView.settings.myLocationButton = true
        mapView.settings.scrollGestures = true
        mapView.settings.zoomGestures = true
        mapView.settings.rotateGestures = true
        mapView.settings.tiltGestures = true
        mapView.isIndoorEnabled = false

        if let mylocation = mapView.myLocation {
          print("User's location: \(mylocation)")
        } else {
          print("User's location is unknown")
        }

//        locationManager.desiredAccuracy = kCLLocationAccuracyBest
//        locationManager.requestAlwaysAuthorization()
//        locationManager.distanceFilter = 50
//        locationManager.startUpdatingLocation()
//        locationManager.delegate = self
        
        return mapView
    }

//    Updates the presented `UIView` (and coordinator) to the latestconfiguration.
    func updateUIView(_ mapView: GMSMapView, context: Context) {
        // Creates a marker in the center of the map.
        marker.position = CLLocationCoordinate2D(latitude: 42.361145, longitude: -71.057083)
        marker.title = "Boston"
        marker.snippet = "USA"
        marker.map = mapView
    }
}

我在上面注释掉的代码是我尝试让 GMSMapView 相机在启动时聚焦在用户设备位置（如 google 开发者页面所说），但我一直收到错误消息“无法在 locationManager.delegate = self

行上将类型 GoogMapView 的值分配给类型 CLLocationManagerDelegate?

我读到我需要利用 UIViewControllerRepresentable 来包装我的上述代码以解决此问题。这是一个包装的例子，有人指给我参考：

struct PageViewController: UIViewControllerRepresentable {
    var controllers: [UIViewController]
    @Binding var currentPage: Int
    
    func makeCoordinator() -> Coordinator {
        Coordinator(self)
    }
    
    func makeUIViewController(context: Context) -> UIPageViewController {
        let pageViewController = UIPageViewController(
            transitionStyle: .scroll,
            navigationOrientation: .horizontal)
        pageViewController.dataSource = context.coordinator
        pageViewController.delegate = context.coordinator

        return pageViewController
    }
    
    func updateUIViewController(_ pageViewController: UIPageViewController, context: Context) {
        pageViewController.setViewControllers(
            [controllers[currentPage]], direction: .forward, animated: true)
    }
    
    class Coordinator: NSObject, UIPageViewControllerDataSource, UIPageViewControllerDelegate {
        var parent: PageViewController
        
        init(_ pageViewController: PageViewController) {
            self.parent = pageViewController
        }
        
        func pageViewController(
            _ pageViewController: UIPageViewController,
            viewControllerBefore viewController: UIViewController) -> UIViewController?
        {
            guard let index = parent.controllers.firstIndex(of: viewController) else {
                return nil
            }
            if index == 0 {
                return parent.controllers.last
            }
            return parent.controllers[index - 1]
        }
        
        func pageViewController(
            _ pageViewController: UIPageViewController,
            viewControllerAfter viewController: UIViewController) -> UIViewController?
        {
            guard let index = parent.controllers.firstIndex(of: viewController) else {
                return nil
            }
            if index + 1 == parent.controllers.count {
                return parent.controllers.first
            }
            return parent.controllers[index + 1]
        }
        
        func pageViewController(_ pageViewController: UIPageViewController, didFinishAnimating finished: Bool, previousViewControllers: [UIViewController], transitionCompleted completed: Bool) {
            if completed,
                let visibleViewController = pageViewController.viewControllers?.first,
                let index = parent.controllers.firstIndex(of: visibleViewController)
            {
                parent.currentPage = index
            }
        }
    }
}

有谁知道如何让我在 GoogMapView.swift 中的地图在启动时以用户位置为中心，方法是将它包装在 UIViewController 中？？

Answer 1

Git 对于任何需要这个的人：

//
//  GoogMapView.swift
//  Landmarks
//
//

import SwiftUI
import UIKit
import GoogleMaps
import GooglePlaces
import CoreLocation
import Foundation



struct GoogMapView: View {
    var body: some View {
        GoogMapControllerRepresentable()
    }
}


class GoogMapController: UIViewController, CLLocationManagerDelegate {
    var locationManager = CLLocationManager()
    var mapView: GMSMapView!
    let defaultLocation = CLLocation(latitude: 42.361145, longitude: -71.057083)
    var zoomLevel: Float = 15.0
    let marker : GMSMarker = GMSMarker()


    override func viewDidLoad() {
        super.viewDidLoad()

        locationManager = CLLocationManager()
        locationManager.desiredAccuracy = kCLLocationAccuracyBest
        locationManager.requestAlwaysAuthorization()
        locationManager.distanceFilter = 50
        locationManager.startUpdatingLocation()
        locationManager.delegate = self

        let camera = GMSCameraPosition.camera(withLatitude: defaultLocation.coordinate.latitude, longitude: defaultLocation.coordinate.longitude, zoom: zoomLevel)
        mapView = GMSMapView.map(withFrame: view.bounds, camera: camera)
        mapView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
        mapView.isMyLocationEnabled = true
        mapView.setMinZoom(14, maxZoom: 20)
        mapView.settings.compassButton = true
        mapView.isMyLocationEnabled = true
        mapView.settings.myLocationButton = true
        mapView.settings.scrollGestures = true
        mapView.settings.zoomGestures = true
        mapView.settings.rotateGestures = true
        mapView.settings.tiltGestures = true
        mapView.isIndoorEnabled = false

//        if let mylocation = mapView.myLocation {
//          print("User's location: \(mylocation)")
//        } else {
//          print("User's location is unknown")
//        }

        marker.position = CLLocationCoordinate2D(latitude: 42.361145, longitude: -71.057083)
        marker.title = "Boston"
        marker.snippet = "USA"
        marker.map = mapView

        // Add the map to the view, hide it until we&#39;ve got a location update.
        view.addSubview(mapView)
//        mapView.isHidden = true

    }

    // Handle incoming location events.
    func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
      let location: CLLocation = locations.last!
      print("Location: \(location)")

      let camera = GMSCameraPosition.camera(withLatitude: location.coordinate.latitude, longitude: location.coordinate.longitude, zoom: zoomLevel)

      if mapView.isHidden {
        mapView.isHidden = false
        mapView.camera = camera
      } else {
        mapView.animate(to: camera)
      }

    }

    // Handle authorization for the location manager.
    func locationManager(_ manager: CLLocationManager, didChangeAuthorization status: CLAuthorizationStatus) {
      switch status {
      case .restricted:
        print("Location access was restricted.")
      case .denied:
        print("User denied access to location.")
        // Display the map using the default location.
        mapView.isHidden = false
      case .notDetermined:
        print("Location status not determined.")
      case .authorizedAlways: fallthrough
      case .authorizedWhenInUse:
        print("Location status is OK.")
      }
    }

    // Handle location manager errors.
    func locationManager(_ manager: CLLocationManager, didFailWithError error: Error) {
      locationManager.stopUpdatingLocation()
      print("Error: \(error)")
    }

}


struct GoogMapControllerRepresentable: UIViewControllerRepresentable {
    func makeUIViewController(context: UIViewControllerRepresentableContext<GMControllerRepresentable>) -> GMController {
        return GMController()
    }

    func updateUIViewController(_ uiViewController: GMController, context: UIViewControllerRepresentableContext<GMControllerRepresentable>) {

    }
}

如何将 swiftUI 视图包装到 UIViewControllerRepresentable 中，以便 Google 地图相机在启动时聚焦于用户的位置？

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