}
}
});
// When a node is collapsed or expanded, ensure the corresponding DisplayNode is kept in Sync
this.addTreeExpansionListener(new TreeExpansionListener() {
public void treeExpanded(TreeExpansionEvent event) {
Object node = event.getPath().getLastPathComponent();
TreeViewWidget.this.setSelectionPath(event.getPath());
if (node instanceof DisplayNode) {
((DisplayNode)node).setOpened_PRIVATE(true);