how to initialise markers on map start up

[kar1981]

Can you please help me understand how I can add markers to the map on map first showing up?

 _kakaoMap = KakaoMap(
      onMapCreated: onMapCreated,
      initialCameraPosition: _kInitialPosition,
      compassEnabled: true,
      mapType: MapType.standard,
      hdMapTileEnabled: true,
      currentLocationTrackingMode: CurrentLocationTrackingMode.trackingModeOff,
      myLocationEnabled: true,
      markers: Set<Marker>.of(markers.values),
    );

void onMapCreated(KakaoMapController controller) async {
      final MapPoint visibleRegion = await controller.getMapCenterPoint();
      setState(() {
        _controller = controller;
        _visibleRegion = visibleRegion;
        addMarkers();
      });
   }

void addMarkers(){
//create some markers here
//add markers to the Map<MarkerId, Marker> markers
...

If I call addMarkers() inside onMapCreated, the app will throw exception:

Unhandled Exception: PlatformException(error, Attempt to invoke virtual method 'void net.daum.mf.map.api.MapView.addPOIItem(net.daum.mf.map.api.MapPOIItem)' on a null object reference, null, java.lang.NullPointerException: Attempt to invoke virtual method 'void net.daum.mf.map.api.MapView.addPOIItem(net.daum.mf.map.api.MapPOIItem)' on a null object reference

Seems like the MapView is not instantiated yet.

If I call addMarkers() from a button (ie: after map fully loads), it works and all the markers are added to the map. I thought that onMapCreated callback is fired after the map has fully loaded, but it seems like this is not working.

Where can I call addMarkers() to add markers automatically without triggering it from a button?

Thanks:)