// Create a ValidationListener and add it to the XMLValidator
// associated with the ODOMEditorContext so that we are notified
// when validation occurs allowing us to refresh and if necessary
// redecorate images that indicate or should not now indicate errors.
final ValidationListener validationListener = new ValidationListener() {
public void validated() {
if (!treeViewer.getControl().isDisposed()) {
treeViewer.getControl().getDisplay().asyncExec(new Runnable() {
public void run() {
// ensure that the widget still exists when this