Mapbox 无法显示设备位置

Question

我有一个带有 Mapbox 的片段，我想在上面显示设备位置。

class SampleMapFragment : Fragment(), PermissionsListener {

    private lateinit var binding: FragmentExploreBinding

    @Inject
    lateinit var permissionsManager: PermissionsManager

    private lateinit var mapboxMap: MapboxMap

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        Mapbox.getInstance(requireContext().applicationContext, getString(R.string.mapbox_token))
    }

    override fun onCreateView(
        inflater: LayoutInflater,
        container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View? {
        if (!::binding.isInitialized) {
            binding = DataBindingUtil.inflate(
                inflater,
                R.layout.fragment_explore,
                container,
                false
            )

            binding.lifecycleOwner = this

            binding.mapView.onCreate(savedInstanceState)
            setUpMap()
        }

        return binding.root
    }

    private fun setUpMap() {
        binding.mapView.getMapAsync { mapboxMap ->
            this.mapboxMap = mapboxMap
            mapboxMap.setStyle(Style.MAPBOX_STREETS) { loadedMapStyle ->
                starLocationTracking(loadedMapStyle)
            }
        }
    }

    private fun starLocationTracking(loadedMapStyle: Style) {
        if (!PermissionsManager.areLocationPermissionsGranted(requireContext())) {
            permissionsManager.requestLocationPermissions(requireActivity())
            return
        }

        initLocationComponent(loadedMapStyle)
    }

    private fun initLocationComponent(loadedMapStyle: Style) {

        val customLocationComponentOptions = LocationComponentOptions.builder(requireActivity())
            .elevation(5f)
            .accuracyAlpha(.6f)
            .accuracyColor(Color.RED)
            .build()

        val locationComponentActivationOptions = LocationComponentActivationOptions.builder(
            requireActivity(),
            loadedMapStyle
        )
            .locationComponentOptions(customLocationComponentOptions)
            .build()

        mapboxMap.locationComponent.apply {
            activateLocationComponent(locationComponentActivationOptions)
            isLocationComponentEnabled = true
            renderMode = RenderMode.COMPASS
            cameraMode = CameraMode.TRACKING
        }
    }

    override fun onExplanationNeeded(permissionsToExplain: MutableList<String>?) {
        // TODO some explanation can be shown here
    }

    override fun onPermissionResult(granted: Boolean) {
        if (granted) mapboxMap.getStyle { loadedStyle -> starLocationTracking(loadedStyle) }
        //else TODO some explanation can be shown here
    }

    fun onMapBoxRequestPermissionsResult(
        requestCode: Int,
        permissions: Array<out String>,
        grantResults: IntArray
    ) = permissionsManager.onRequestPermissionsResult(requestCode, permissions, grantResults)

    override fun onStart() {
        super.onStart()
        binding.mapView.onStart()
    }

    override fun onResume() {
        super.onResume()
        binding.mapView.onResume()
    }

    override fun onPause() {
        super.onPause()
        binding.mapView.onPause()
    }

    override fun onStop() {
        super.onStop()
        binding.mapView.onStop()
    }

    override fun onDestroy() {
        super.onDestroy()
        releaseMapResources()
        releasePermissionsManagerListener()
    }

    private fun releaseMapResources() {
        binding.mapView.onDestroy()
    }

    private fun releasePermissionsManagerListener() {
        permissionsManager.listener = null
    }

    override fun onSaveInstanceState(outState: Bundle) {
        super.onSaveInstanceState(outState)
        binding.mapView.onSaveInstanceState(outState)
    }

    override fun onLowMemory() {
        super.onLowMemory()
        binding.mapView.onLowMemory()
    }
}

我用 2 个真实设备和 1 个模拟器测试了上面的实现。该解决方案适用于 Android 10 设备。找到用户位置，即使关闭定位服务并在地图后再次打开它，也是可见的。

但有时找不到位置，有时需要很长时间，在尝试使用 Android 9 和 Android 7 设备时，甚至在地图可见之前位置服务就已经准备就绪。

这可能是什么问题？任何帮助将不胜感激。

Answer 1

"But location is sometimes not found, sometimes it take very long, even the location services are ready before the map is visible while trying with Android 9 and Android 7 devices."

这听起来好像设备试图从 GPS 传感器获取位置，但需要很长时间才能检索到。使用较新的设备和 Android 10 本地化已得到改进，因此这可以解释您所看到的内容。

要了解发生了什么，我建议实施 Android FusedLocationProvider 并将行为与 Mapbox SDK (locationComponent) 包装的行为进行比较。

此外，请检查您使用 Android 10 获得的 "snappy" 位置是否实际上是从 GPS 传感器检索到的，或者如果它是 "just" 最后已知的位置，那是由 Android.

缓存

Mapbox 无法显示设备位置

Mapbox is unable to show device location

android

android-location

mapbox

mapbox-gl

mapbox-android