if (evt.getNewValue() != null) {
		if (component == firstInvisibleAncestor) {
		    addListeners(component, false);
		    if (firstInvisibleAncestor == null) {
			fireAncestorAdded(root, AncestorEvent.ANCESTOR_ADDED,
					  component, component.getParent());
		    }
		}
	    } else {
		boolean needsNotify = firstInvisibleAncestor == null;
		Container oldParent = (Container)evt.getOldValue();

		removeListeners(oldParent);
		firstInvisibleAncestor = component;
		if (needsNotify) {
		    fireAncestorRemoved(root, AncestorEvent.ANCESTOR_REMOVED,
					component, oldParent);
		}
	    }
	}
    }
}