/**
  * {@inheritDoc}
  *
  * @see SourcesPopupEvents#removePopupListener(PopupListener)
  */
 public void removePopupListener(PopupListener listener) {
   popupListeners.remove(listener);
 }
 /**
  * {@inheritDoc}
  *
  * @see com.google.gwt.user.client.ui.PopupListener#onPopupClosed(PopupPanel, boolean)
  */
 public void onPopupClosed(PopupPanel sender, boolean autoClosed) {
   if (sender == dialog) {
     popupListeners.firePopupClosed(this, autoClosed);
   }
 }
 /**
  * {@inheritDoc}
  *
  * @see SourcesPopupEvents#addPopupListener(PopupListener)
  */
 public void addPopupListener(PopupListener listener) {
   popupListeners.add(listener);
 }