steps to reproduce

1. load the attached excel file in firefox (or chrome)

   <spreadsheet id="ss" src="/WEB-INF/issue/1212-5.xlsx" maxVisibleRows="800" maxVisibleColumns="100" width="100%" 
   		height="90%" preloadColumnSize="5" preloadRowSize="5"
   		showContextMenu="true" showSheetbar="true" showToolbar="true" showFormulabar="true"/>
   

2. click the 2nd sheet

actual

a javascript error is thrown.

setAttr
this.cells[0] is undefined (TypeError)
zk.override.prepareFilterBtns_ @ zssex.wpd:22
zk.override._prepareAutoFilterBtns @ zssex.wpd:22
zk.override._prepareAllFilterBtns @ zssex.wpd:22
zk.override.bind_ @ zssex.wpd:22
zk.Widget.zk.$extends.bindChildren_ @ zk.wpd:16633
zk.Widget.zk.$extends.bind_ @ zk.wpd:16603
zk.Object.$supers @ zk.wpd:10629
zss.CellBlockCtrl.zk.$extends.bind_ @ zss.wpd:10
zk.Widget.zk.$extends.bindChildren_ @ zk.wpd:16633
zk.Widget.zk.$extends.bind_ @ zk.wpd:16603
zk.Object.$supers @ zk.wpd:10629
zss.Panel.zk.$extends.bind_ @ zss.wpd:27
zk.Object.$supers @ zk.wpd:10629
zss.TopPanel.zk.$extends.bind_ @ zss.wpd:29
zk.Widget.zk.$extends.bind @ zk.wpd:16566
zk.Widget.zk.$extends.replaceChildHTML_ @ zk.wpd:16417
zk.Widget.zk.$extends.replaceHTML @ zk.wpd:16328
zk.Widget.zk.$extends.replaceWidget @ zk.wpd:15810
zss.SSheetCtrl.zk.$extends.doSheetSelected @ zss.wpd:37
zss.Spreadsheet.zk.$extends.$define.sheetId @ zss.wpd:2
(anonymous function) @ zk.wpd:9897
zk.copy._set2 @ zk.wpd:10331
zk.Widget.zk.$extends.set @ zk.wpd:15568
zAu.cmd1.setAttr @ zk.wpd:20279
doProcess @ zk.wpd:19292
doCmdsNow @ zk.wpd:19532
zAu._doCmds @ zk.wpd:19780
afterResponse @ zk.wpd:19424
onResponseReady @ zk.wpd:19421
XMLHttpRequest.send (async)
ajaxSendNow @ zk.wpd:19484
zAu.sendNow @ zk.wpd:19938
(anonymous function) @ zk.wpd:19463
setTimeout (async)
ajaxSend2 @ zk.wpd:19463
ajaxSend @ zk.wpd:19457
zAu.send @ zk.wpd:19698
zk.Widget.zk.$extends.sendAU_ @ zk.wpd:17069
zk.Object.$supers @ zk.wpd:10655
zss.Spreadsheet.zk.$extends.sendAU_ @ zss.wpd:2
zk.Widget.zk.$extends.fireX @ zk.wpd:17048
zk.Widget.zk.$extends.fire @ zk.wpd:17077
zss.SheetSelector.zk.$extends.doSelectSheet @ zss.wpd:36
zss.SheetSelector.zk.$extends._onSelectSheet @ zss.wpd:36
(anonymous function) @ zk.wpd:10582
zk.Widget.zk.$extends.fireX @ zk.wpd:17029
_fireClick @ zk.wpd:14907
zk.Widget.zk.$extends.doClick_ @ zk.wpd:17211
zk.Object.$supers @ zk.wpd:10655
zul.Widget.zk.$extends.doClick_ @ zk.wpd:22253
zk.Object.$supers @ zk.wpd:10655
zul.tab.Tab.zk.$extends.doClick_ @ zul.tab.wpd:910
zk.Object.$supers @ zk.wpd:10629
zss.SheetTab.zk.$extends.doClick_ @ zss.wpd:36
_doEvt @ zk.wpd:18762
(anonymous function) @ zk.wpd:18958
jQuery.event.dispatch @ zk.wpd:5162
elemData.handle @ zk.wpd:4833


debug information

• if we remove the filter, there is no js error.

workaround

• specify a bigger preloadColumnSize (> 7) or no specify can resolve this issue