如何在谷歌地图上获取方向选项

Question

我通过使用google map Api显示客户机构位置来创建google map 在我的ViewController中，我使用以下代码显示机构。

但是我不知道如何在mapView上获得方向选项。

import UIKit

import GoogleMaps

class viewController: UIViewController
{
    @IBOutlet weak var MapView: GMSMapView!

    override func viewDidLoad()
    {
        super.viewDidLoad()
        load()
    }

    func load() {
        //map
        let camera = GMSCameraPosition.camera(withLatitude: 18.435121, longitude: -78.439278, zoom: 15.0)
        MapView.camera = camera

        //marker
        let marker = GMSMarker()
        marker.position = CLLocationCoordinate2D(latitude: 18.435121, longitude: -78.439278)

        marker.map = MapView
    }
}

在AppDelegate中

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool
{
    GMSServices.provideAPIKey("APIkey")
}

我想要下面的图片

enter image description here