helper.stopAdvancedFeatures();
// vertex selection OR geometry selection should not both happen so make them a mutual exclusion behaviour
helper.startMutualExclusiveList();
helper.startOrderedList(false);
AddVertexWhileCreatingBehaviour addVertexWhileCreatingBehaviour = new AddVertexWhileCreatingBehaviour();
addVertexWhileCreatingBehaviour.setEditValidator(new PolygonCreationValidator());
helper.add( addVertexWhileCreatingBehaviour);
helper.add( new AcceptWhenOverFirstVertexBehaviour());
helper.stopOrderedList();
helper.startAdvancedFeatures();
helper.add(new SelectVertexOnMouseDownBehaviour());