// Listen for expand/collapse so we can redraw ourselves
// TF:24/06/2008:Extracted this code into a named variable
this.tree.addTreeExpansionListener(expansionListener);
// Disable the collapse if the controls are hidden. CraigM 03/10/2007.
this.tree.addTreeWillExpandListener(new TreeWillExpandListener() {
public void treeWillCollapse(TreeExpansionEvent event) throws ExpandVetoException {
if (OutlineField.this.isControlsDisplayed() == false) {
ExpandVetoException errorVar = new ExpandVetoException(event);
ErrorMgr.addError(errorVar);
throw errorVar;