标记未在 Android 中的地图上显示

Question

我刚刚创建了一个 Google 地图片段。标记 sydney 没有显示...我忘了添加什么吗？我已经添加了我的 Google 地图密钥

class fragment_map : Fragment() {

    private val callback = OnMapReadyCallback { googleMap ->
        /**
         * Manipulates the map once available.
         * This callback is triggered when the map is ready to be used.
         * This is where we can add markers or lines, add listeners or move the camera.
         * In this case, we just add a marker near Sydney, Australia.
         * If Google Play services is not installed on the device, the user will be prompted to
         * install it inside the SupportMapFragment. This method will only be triggered once the
         * user has installed Google Play services and returned to the app.
         */
        val sydney = LatLng(-34.0, 151.0)
        googleMap.addMarker(MarkerOptions().position(sydney).title("Marker in Sydney"))
        googleMap.moveCamera(CameraUpdateFactory.newLatLng(sydney))
    }

    override fun onCreateView(
        inflater: LayoutInflater,
        container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View? {
        return inflater.inflate(R.layout.fragment_map, container, false)
    }

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)
        val mapFragment = childFragmentManager.findFragmentById(R.id.map) as SupportMapFragment?
        mapFragment?.getMapAsync(callback)
    }
}

Answer 1

您的 onMapReady 似乎不完整。试试这个吧？

class fragment_map : Fragment() {

    private val callback = OnMapReadyCallback { googleMap ->
        override fun onMapReady(googleMap: GoogleMap) {
            mMap = googleMap

            val boundsBuilder = LatLngBounds.Builder()
            val sydney = LatLng(-34.0, 151.0)
            boundsBuilder.include(latlng)

            Map.addMarker(MarkerOptions().position(latlng).title("Sydney"))
            mMap.moveCamera(CameraUpdateFactory.newLatLngBounds(boundsBuilder.build(), 1000, 1000, 0))
        }


    }

    override fun onCreateView(
        inflater: LayoutInflater,
        container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View? {
        return inflater.inflate(R.layout.fragment_map, container, false)
    }

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)
        val mapFragment = childFragmentManager.findFragmentById(R.id.map) as SupportMapFragment?
        mapFragment?.getMapAsync(callback)
    }
}