How can I draw a Polyline that "follows" my device's location?

Question

I am developing a canoe trip planning and tracking application, and I would like to track the progress on the map with a Polyline that follows my device's location. Here is the code I have so far:

var polylineTest by mutableStateOf<ArrayList<LatLng>>(arrayListOf())

GoogleMap(
    properties = MapProperties(isMyLocationEnabled = true),
    cameraPositionState = cameraPositionState,
    modifier = Modifier
        .padding(
            bottom = padding.calculateBottomPadding(),
        ),
    onMapLongClick = { loc ->
        viewModel.onEvent(MapViewEvent.OnMapLongClick(loc))

    },
    uiSettings = uiSettings,

) {
    viewModel.getSpotsFromDB(ongoing = true, viewModel.currentDayID).forEach() { spot ->
        Log.i("MapViewScreen", "dayID: ${viewModel.currentDayID}, spot: $spot")
        Marker(
            state = MarkerState(
                position = LatLng(spot.Latitude, spot.Longitude)
            ),
            title = spot.Name,
            snippet = spot.Description,
            onInfoWindowClick = {
                viewModel.onEvent(MapViewEvent.OnSpotClick(spot.ID!!))

            }
        )
    }
    Log.i("MapViewScreen", "points: ${viewModel.polylineTest}")
    Polyline(points = viewModel.polylineTest)
}

What could I be doing wrong here? If more info needed I'll provide of course. Kind regards

I know for sure that the polylineTest variable changes correctly because the Log message correctly shows the ArrayList getting bigger with every location update. My problem is that I cannot see anything change on the map itself immediately, no polyline is being drawn as my location changes, but when I long click the map to add a spot, and go back, it renders the polyline. If I call the Polyline composable with a static list of LatLngs it does show up on the map correctly, but not if I call it with viewModel.polylineTest.

How could I make it so the polyline is being drawn immediately as the location changes? Also preferably I'd like it to not draw over the existing polyline. I'm open to suggestions because I am kinda lost :D