switchType.getSelectionModel().selectedItemProperty().addListener(new ChangeListener<String>() {
@Override
public void changed(ObservableValue<? extends String> observable, String oldValue, String newValue) {
if(! "<NONE>".equals(newValue) ) {
ACenterSwitchAnimation a = transitionService.getAnimations().get(newValue);
if( a != null ) {
a.animate(switchPreview, switchPreview.getCenter() == view1 ? view2 : view1);
updateTransitionPreference(newValue);
} else {
updateTransitionPreference(null);
}
} else {