docs: public void init(BaseField field, Field sourceField, Object sourceString, boolean bInitIfSourceNull, boolean bOnlyInitIfDestNull)
      {
          super.init(field);
          m_objSource = sourceString;
          m_fldSource = (BaseField)sourceField;
          m_bInitIfSourceNull = bInitIfSourceNull;
          m_bOnlyInitIfDestNull = bOnlyInitIfDestNull;
          
          m_bScreenMove = false;
          m_bInitMove = true;     // Only respond to init
          m_bReadMove = false;
      }