refer to zul code

<zk>
<intbox>
<attribute name="onOK">
int rows = self.getValue();
System.out.println("set max rows: " + (ss.getMaxrows() + 50));
ss.setMaxrows(ss.getMaxrows() + 50);
</attribute>
</intbox>
<spreadsheet id="ss" maxrows="50" src="/xls/test.xlsx" height="100%" width="100%"></spreadsheet>
</zk>