private void verifyChangedField(GridField field, String columnName) {
   ArrayList<String> list = field.getDependentOn();
   if (list.contains(columnName)) {
     if (field.getLookup() instanceof MLookup) {
       MLookup mLookup = (MLookup) field.getLookup();
       // if the lookup is dynamic (i.e. contains this columnName as variable)
       if (mLookup.getValidation().indexOf("@" + columnName + "@") != -1) {
         log.fine(columnName + " changed - " + field.getColumnName() + " set to null");
         // invalidate current selection
         field.setValue(null, true);
       }
     }
   }
 }
  /** @param gridField */
  public WLocatorEditor(GridField gridField) {
    super(new EditorBox(), gridField);
    m_mLocator = (MLocatorLookup) gridField.getLookup();

    getComponent().setButtonImage("/images/Locator10.png");

    setDefault_Locator_ID(); // set default locator, teo_sarca [ 1661546 ]

    m_WindowNo = gridField.getWindowNo();

    if (gridField != null) {
      popupMenu = new WEditorPopupMenu(true, true, false);
      if (gridField != null && gridField.getGridTab() != null) {
        WRecordInfo.addMenu(popupMenu);
      }
      getComponent().setContext(popupMenu.getId());
    }
  }