replaceMarker method
Finds the old marker with the given item and replaces it with the new marker. Do not forget to call setRepaint()
Implementation
void replaceMarker(var item, BasicMarker newMarker) {
Marker? oldMarker = getMarkerWithItem(item);
if (oldMarker != null) {
_markers.remove(item);
_previousMarkers.remove(oldMarker);
oldMarker.dispose();
}
_markers[item] = newMarker;
if (_previousBoundingBox != null &&
newMarker.shouldPaint(_previousBoundingBox!, _previousZoomLevel))
_previousMarkers.add(newMarker);
}