code: @Override
    public void layoutParts() {
      setVgrow(treeView, Priority.ALWAYS);
      getChildren().addAll(searchFld, treeView);
  
      treeView.setRoot(rootItem);
      // TreeSearchView requires a RootItem, but in this case it's not desired to have it visible.
      treeView.setShowRoot(false);
      treeView.getRoot().setExpanded(true);
      treeView.setStyle("-fx-background-color:transparent;"); // Remove border
    }
docs: {@inheritDoc}