Gridx/Grid DOJO : issue with checkbox and filter : when filter is used, checkboxes get uncheked

I am using gridx/grid to make grid where for checkboxes, "IndirectSelect and ExtendedSelect" are used. The issue is, ****when I select some checkboxes and then type something in filter, all checked checkboxes become unchecked****.

Please help in any way the checkboxes checked state can be maintained when filter is used.

Please help. Thanks in Advance.

Following is the code to create grid:

this.grid=new Grid({ id: 'grid', cacheClass: Cache, store: this.store, structure: this.layout, vScrollerBuffSize: 300, selectRowTriggerOnCell: true, barTop: [ DropDownPager, {pluginClass: QuickFilter, style: 'text-align: right;'} ], barBottom: [ LinkSizer, {pluginClass: Summary, style:'text-align:center'}, {pluginClass: LinkPager, style: 'text-align: right;'} ], modules: [ extendedSelect, RowHeader, IndirectSelect, CellWidget, ColumnResizer, Bar, VirtualVScroller, {
moduleClass: Pagination, initialPageSize:10 }, Filter, FilterBar ], autoHeight: false }, document.createElement('div'));