XPages:How to set dojo grid item selected after XSP.partialRefreshPost

Question

I am using Dojo EnhancedGrid and would like to set an item selected after calling XSP.partialRefreshPost or XSP.partialRefreshGet

 var store = dataGrid.store;
    index = grid.selection.selectedIndex;
    var item = dataGrid.getItem(index);
    var id = store.getValue(item, "@unid");
    var remoteMethod = myRPC.sortGridPosition(index + 'DOWN');
    remoteMethod.addCallback(function(response){
        // handle whatever came back from the server

        XSP.partialRefreshPost("#{id:gridDiv}",{
            onComplete: function () {
            grid.selection.setSelected(response, true);
            grid.selection.setSelected(parseInt(index), false);
        }   
        });
    }); 

but i keep geting the error cannot find focusView of undefined, how can i set index selected after XSP.partialRefreshPost?