private void disableCodeBoxes(Treeitem item, boolean disabled) {
Treerow row = item.getTreerow();
InputElement codeBox = (InputElement) ((Treecell) row.getChildren()
.get(1)).getChildren().get(0);
codeBox.setDisabled(disabled);
codeBox.invalidate();
Set<Treeitem> childrenSet = new HashSet<Treeitem>();
Treechildren children = item.getTreechildren();
if (children != null) {
childrenSet.addAll((Collection<Treeitem>) children.getItems());