如何在iOS Swift中绘制CurrentLocation(locationStart)到SearchedLocation(locationEnd)在GoogleMaps中的路由

import UIKit
import GoogleMaps
import CoreLocation

class ViewController: UIViewController, CLLocationManagerDelegate {

    @IBOutlet weak var mapView: GMSMapView!
    
    let locationManager = CLLocationManager()
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // 设置CLLocationManager代理
        locationManager.delegate = self
        
        // 请求用户位置权限
        locationManager.requestWhenInUseAuthorization()
        
        // 开始更新用户位置
        locationManager.startUpdatingLocation()
    }
    
    // CLLocationManager代理方法，获取用户位置
    func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
        if let location = locations.first {
            // 获取到用户当前位置坐标
            
            // 停止更新用户位置
            locationManager.stopUpdatingLocation()
            
            // 设置地图视图的显示区域为用户当前位置
            let camera = GMSCameraPosition.camera(withLatitude: location.coordinate.latitude, longitude: location.coordinate.longitude, zoom: 12.0)
            mapView.camera = camera
            
            // 在地图上添加一个标记，表示用户当前位置
            let marker = GMSMarker()
            marker.position = CLLocationCoordinate2D(latitude: location.coordinate.latitude, longitude: location.coordinate.longitude)
            marker.title = "Current Location"
            marker.map = mapView
            
            // 获取目标位置的坐标
            let destinationCoordinate = CLLocationCoordinate2D(latitude: 37.7749, longitude: -122.4194) // 替换为你的目标位置坐标
            
            // 绘制路线
            drawRoute(from: location.coordinate, to: destinationCoordinate)
        }
    }
    
    // 使用Google Maps Directions API绘制路线
    func drawRoute(from startCoordinate: CLLocationCoordinate2D, to endCoordinate: CLLocationCoordinate2D) {
        let origin = "\(startCoordinate.latitude),\(startCoordinate.longitude)"
        let destination = "\(endCoordinate.latitude),\(endCoordinate.longitude)"
        let apiKey = "YOUR_API_KEY" // 替换为你的Google Maps API密钥
        
        let url = URL(string: "https://maps.googleapis.com/maps/api/directions/json?origin=\(origin)&destination=\(destination)&key=\(apiKey)")!
        
        URLSession.shared.dataTask(with: url) { (data, response, error) in
            if let data = data {
                do {
                    let json = try JSONSerialization.jsonObject(with: data, options: []) as! [String: Any]
                    
                    if let routes = json["routes"] as? [[String: Any]] {
                        if let route = routes.first {
                            if let polyline = route["overview_polyline"] as? [String: Any] {
                                if let points = polyline["points"] as? String {
                                    // 解码路线坐标点
                                    let path = GMSPath(fromEncodedPath: points)
                                    
                                    // 创建GMSPolyline对象并添加到地图上
                                    let polyline = GMSPolyline(path: path)
                                    polyline.strokeWidth = 3.0
                                    polyline.strokeColor = UIColor.blue
                                    polyline.map = self.mapView
                                }
                            }
                        }
                    }
                } catch {
                    print("Error parsing JSON: \(error)")
                }
            }
        }.resume()
    }
}