@Nullable
 public String getSelectedScopeName() {
   final JComboBox combo = getComboBox();
   int idx = combo.getSelectedIndex();
   return idx < 0 ? null : ((ScopeDescriptor) combo.getSelectedItem()).getDisplay();
 }
 @Nullable
 public SearchScope getSelectedScope() {
   final JComboBox combo = getComboBox();
   int idx = combo.getSelectedIndex();
   return idx < 0 ? null : ((ScopeDescriptor) combo.getSelectedItem()).getScope();
 }