Add marker aka symbols not working

[BwesShr]

I have recently tried to implement the mapbox in flutter and I am trying to add symbols and route to the mapbox map. But no symbols are displayed in the screen.
mapController.addSymbol(
SymbolOptions(
geometry: LatLng(
latitude,
longitude,
),
iconImage: driverIcon,
),
);

[TimothySealy]

Hi @BwesShr, which platform are you talking about? Android or iOS. For iOS there is an open PR (#79) for Symbols.

[fauzipadlaw]

I'm working on Android, not working as well

[TimothySealy]

Hi @fauzipadlaw, are you adding a custom symbol or a default one? If you could provide a code snippet it would really help.

Note that custom symbols have been implemented in PR #79 which has not been merged yet.

[fauzipadlaw]

Hi @TimothySealy, I use the default.

in state:

void _onMapCreated(MapboxMapController controller) {
    this.controller = controller;
    controller.onSymbolTapped.add(_onSymbolTapped);
    this.controller.addSymbol(
          SymbolOptions(
              geometry: LatLng(
                _getLat(),
                _getLng(),
              ),
              iconImage: "airport-15"),
        );
  }

MapboxMap(
                          onMapCreated: _onMapCreated,
                          myLocationEnabled: true,
                          initialCameraPosition: CameraPosition(
                              target: LatLng(_getLat(), _getLng()), zoom: 18),
                        )

[TimothySealy]

Just to be sure, if you run the example application do you see a symbol on the map?

I have just tested your snippet by modifying the example app (specifically the "Place symbol" page) and it seems to work but when opening the "Place symbol" for the second time I get the following error (which has also been reported here #104):

E/MethodChannel#plugins.flutter.io/mapbox_maps_3(12492): java.lang.NullPointerException: Attempt to invoke virtual method 'com.mapbox.mapboxsdk.plugins.annotation.Annotation com.mapbox.mapboxsdk.plugins.annotation.SymbolManager.create(com.mapbox.mapboxsdk.plugins.annotation.Options)' on a null object reference
E/MethodChannel#plugins.flutter.io/mapbox_maps_3(12492): 	at com.mapbox.mapboxgl.SymbolBuilder.build(SymbolBuilder.java:25)
E/MethodChannel#plugins.flutter.io/mapbox_maps_3(12492): 	at com.mapbox.mapboxgl.MapboxMapController.onMethodCall(MapboxMapController.java:406)
E/MethodChannel#plugins.flutter.io/mapbox_maps_3(12492): 	at io.flutter.plugin.common.MethodChannel$IncomingMethodCallHandler.onMessage(MethodChannel.java:231)
E/MethodChannel#plugins.flutter.io/mapbox_maps_3(12492): 	at io.flutter.embedding.engine.dart.DartMessenger.handleMessageFromDart(DartMessenger.java:96)
E/MethodChannel#plugins.flutter.io/mapbox_maps_3(12492): 	at io.flutter.embedding.engine.FlutterJNI.handlePlatformMessage(FlutterJNI.java:645)
E/MethodChannel#plugins.flutter.io/mapbox_maps_3(12492): 	at android.os.MessageQueue.nativePollOnce(Native Method)
E/MethodChannel#plugins.flutter.io/mapbox_maps_3(12492): 	at android.os.MessageQueue.next(MessageQueue.java:326)
E/MethodChannel#plugins.flutter.io/mapbox_maps_3(12492): 	at android.os.Looper.loop(Looper.java:160)
E/MethodChannel#plugins.flutter.io/mapbox_maps_3(12492): 	at android.app.ActivityThread.main(ActivityThread.java:6669)
E/MethodChannel#plugins.flutter.io/mapbox_maps_3(12492): 	at java.lang.reflect.Method.invoke(Native Method)
E/MethodChannel#plugins.flutter.io/mapbox_maps_3(12492): 	at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
E/MethodChannel#plugins.flutter.io/mapbox_maps_3(12492): 	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)``` 

[MATTYGILO]

Having the same issue, has this been solved yet??

[tobrun]

@fauzipadlaw

I updated the place_symbol.dart with:

  void _onMapCreated(MapboxMapController controller) {
    this.controller = controller;
    controller.onSymbolTapped.add(_onSymbolTapped);
    this.controller.addSymbol(
          SymbolOptions(
              geometry: LatLng(-33.840002, 151.204478),
              iconImage: "airport-15"),
        );
  }

And I'm seeing the symbol correclty loaded and not hitting exceptions mentioned here:

Happy to take another look if a full reproducible example is provided.

[tobrun]

@BwesShr what is the value of driver icon? Does this icon image exist in your style?

[fauzipadlaw]

@tobrun it is working now

[mopfattn]

This issue came back with 0.0.5 and it seems to be a timing issue.

I get this error when adding a symbol in the _onMapCreated callback, but it works when launching a timer to add the symbols later:

  void onMapCreated(MapboxMapController mapboxMapController) {
    ...
    var options = SymbolOptions(...);
    Timer(Duration(seconds: 1), () => mapboxMapController.addSymbol(options));
    setState(() {});
  }

[m0nac0]

@mopfattn You should only add symbols/lines/circles after the onStyleLoadedCallback has been fired (or in that callback), I think this is not sufficiently documented though

[tobrun]

I think this is not sufficiently documented though

Agreed, we also need to update our internal examples for this as well