code: public boolean printData(PrintWriter out, int iPrintOptions)
      {
          String strFieldName = this.getScreenField().getSFieldParam();
          String strButtonDesc = ((SButtonBox)this.getScreenField()).getButtonDesc();
          if ((strButtonDesc == null)
              && (((SButtonBox)this.getScreenField()).getImageButtonName() != null))
          {
              if (this.getScreenField().getParentScreen() instanceof GridScreen)
              { // These are command buttons such as "Form" or "Detail"
                  GridScreen gridScreen = (GridScreen)this.getScreenField().getParentScreen();
                  Record record = gridScreen.getMainRecord();
                  String strBookmark = DBConstants.BLANK;
                  try {
                      strBookmark = record.getHandle(DBConstants.OBJECT_ID_HANDLE).toString();
                  } catch (DBException ex)    {
                      ex.printStackTrace();
                  }
                  if (this.isSingleDataImage())
                  	strBookmark = this.getScreenField().getConverter().toString();
                  
                  out.println("    " + Utility.startTag(strFieldName) + strBookmark + Utility.endTag(strFieldName));
                  return true;
              }
              else
                  return super.printData(out, iPrintOptions);
          }
          else
              return super.printData(out, iPrintOptions);
      }
docs: Display this field in html input format.