iOS端Mapbox导航语音重复问题排查求助

在iOS端使用Mapbox逐向导航时，需在导航激活状态下添加途经点。通过addSpots方法为地图添加点图层后，点显示正常，但出现以下问题：

• 关闭导航后重新打开，语音播报会重复叠加，关闭再打开的次数越多，语音重复层数越多
• 移除addSpots方法后，语音重复问题消失

已做排查与尝试 #

• 推测控制器关闭时导航未正确终止，新会话与旧会话发生重叠
• 尝试在导航控制器dismiss时调用navigationServices.stop()，但无效果

相关代码 #

import Foundation
import UIKit
import XamoomSDK
import MBProgressHUD
import FirebaseAuth
import NotificationCenter
import MapboxDirections
import MapboxCoreNavigation
import MapboxNavigation
import MapboxMaps
import CoreLocation
import MBProgressHUD

class BasicViewController: UIViewController {
    
    var wayPoint: [Waypoint] = []
    var spots: [XMMSpot] = []
    var customImageMarker: UIImage?
    var layer: [String] = []
    
    convenience init(waypoints: [Waypoint], spots: [XMMSpot], customImageMarker: UIImage, layer: [String]) {
        self.init(nibName: nil, bundle: nil)
        self.wayPoint = waypoints
        self.spots = spots
        self.customImageMarker = customImageMarker
        self.layer = layer
    }
    
    override func viewDidLoad() {
        super.viewDidLoad()
        requestRoute()
    }
    
    func requestRoute() {
        let navigationRoutOptions = NavigationRouteOptions(waypoints: wayPoint)
        
        Directions.shared.calculate(navigationRoutOptions) { [weak self] (_, result) in
            switch result {
            case .failure(let error):
                print(error.localizedDescription)
            case .success(let response):
                guard let strongSelf = self else {
                    return
                }
                
                let navigationService = MapboxNavigationService(routeResponse: response, routeIndex: 0, routeOptions: navigationRoutOptions, credentials: NavigationSettings.shared.directions.credentials, simulating: .none)
                
                let navigationOptions = NavigationOptions(navigationService: navigationService)
                let navigationViewController = NavigationViewController(for: response, routeIndex: 0, routeOptions: navigationRoutOptions,
                                                                        navigationOptions: navigationOptions)
                
                navigationViewController.delegate = strongSelf
                
                self?.addSpots(navViewController: (navigationViewController))
                
                navigationViewController.modalPresentationStyle = .fullScreen
                navigationViewController.routeLineTracksTraversal = true
                
                strongSelf.present(navigationViewController, animated: true, completion: nil)
            }
        }
    }
    
    func addSpots(navViewController: NavigationViewController) {
        navViewController.navigationMapView?.mapView.mapboxMap.onEvery(event: .styleLoaded) {  _ in
          for spot in self.spots {
              let style = navViewController.navigationMapView?.mapView.mapboxMap.style
            try? style?.addImage((self.customImageMarker!), id: "markerimage", stretchX: [], stretchY: [])

            let someCoordinate = CLLocationCoordinate2DMake(spot.latitude, spot.longitude)
            let point = Point(someCoordinate)

            var feature = Feature(geometry: Geometry.point(point))
            feature.identifier = .string(spot.name)

            var source = GeoJSONSource()
            source.data = .feature(feature)
            try? navViewController.navigationMapView?.mapView.mapboxMap.style.addSource(source, id: spot.name)
            self.layer.append(spot.name)

            var layer = SymbolLayer(id: spot.name)
            layer.source = spot.name
            layer.iconImage = .constant(.name("markerimage"))
            layer.iconAnchor = .constant(.bottom)
            layer.textField = .constant(spot.name)
            layer.iconAllowOverlap = .constant(true)
            try? navViewController.navigationMapView?.mapView.mapboxMap.style.addLayer(layer)
          }
        }
    }
}

extension BasicViewController: NavigationViewControllerDelegate {
    func navigationViewControllerDidDismiss(_ navigationViewController: NavigationViewController, byCanceling canceled: Bool) {
        dismiss(animated: true, completion: nil)
    }
}

下一步排查方案 #

1. 清理重复的事件监听
   addSpots中使用onEvery(event: .styleLoaded)会重复注册事件监听，即使旧导航关闭，监听仍可能绑定在地图实例上。需保存监听token并在导航关闭时移除：

   // 新增属性保存监听token
   var styleLoadedToken: Cancelable?
   
   func addSpots(navViewController: NavigationViewController) {
       styleLoadedToken = navViewController.navigationMapView?.mapView.mapboxMap.onEvery(event: .styleLoaded) { [weak self] _ in
           // 原有图层添加逻辑
       }
   }
   
   // 在导航关闭时移除监听
   func navigationViewControllerDidDismiss(_ navigationViewController: NavigationViewController, byCanceling canceled: Bool) {
       styleLoadedToken?.cancel()
       dismiss(animated: true, completion: nil)
   }
   

2. 导航关闭时彻底清理图层资源
   每次导航关闭时，移除之前添加的所有source、layer和图片资源，避免旧资源残留：

   func navigationViewControllerDidDismiss(_ navigationViewController: NavigationViewController, byCanceling canceled: Bool) {
       guard let style = navigationViewController.navigationMapView?.mapView.mapboxMap.style else {
           dismiss(animated: true, completion: nil)
           return
       }
       // 移除所有自定义图层和数据源
       for layerId in self.layer {
           style.removeLayer(withId: layerId)
           style.removeSource(withId: layerId)
       }
       self.layer.removeAll()
       // 移除自定义图片
       style.removeImage(withId: "markerimage")
       // 停止并销毁导航服务
       navigationViewController.navigationService.shutdown()
       dismiss(animated: true, completion: nil)
   }
   

3. 修正导航服务的生命周期管理
   将navigationService声明为类属性，确保在关闭时能准确终止并释放：

   class BasicViewController: UIViewController {
       var navigationService: MapboxNavigationService?
       // ...其他属性
       
       func requestRoute() {
           // ...原有逻辑
           self.navigationService = MapboxNavigationService(routeResponse: response, routeIndex: 0, routeOptions: navigationRoutOptions, credentials: NavigationSettings.shared.directions.credentials, simulating: .none)
           let navigationOptions = NavigationOptions(navigationService: self.navigationService!)
           // ...后续逻辑
       }
       
       func navigationViewControllerDidDismiss(_ navigationViewController: NavigationViewController, byCanceling canceled: Bool) {
           navigationService?.shutdown()
           navigationService = nil
           dismiss(animated: true, completion: nil)
       }
   }
   

4. 避免重复添加图片资源
   addSpots中每次循环都调用addImage会重复添加同名图片，改为仅添加一次：

   func addSpots(navViewController: NavigationViewController) {
       navViewController.navigationMapView?.mapView.mapboxMap.onEvery(event: .styleLoaded) { [weak self] _ in
           guard let self = self, let style = navViewController.navigationMapView?.mapView.mapboxMap.style else { return }
           // 检查图片是否已存在，不存在再添加
           if style.image(withId: "markerimage") == nil {
               try? style.addImage(self.customImageMarker!, id: "markerimage", stretchX: [], stretchY: [])
           }
           // 原有添加source和layer的逻辑
       }
   }
   

内容的提问来源于stack exchange，提问作者Ivan Magda