if (rowValueChangeHandlerReg != null) {
rowValueChangeHandlerReg.removeHandler();
rowValueChangeHandlerReg = null;
}
rowCountChangeHandlerReg = tableModel.addRowCountChangeHandler(new RowCountChangeHandler() {
public void onRowCountChange(RowCountChangeEvent event) {
int pageCount = getPageCount();
if (pageCount != oldPageCount) {
fireEvent(new PageCountChangeEvent(oldPageCount, pageCount));
oldPageCount = pageCount;