Simple Slickgrid sorting doesn't work

Question

Is there obvious reason why this Slickgrid example shouldn't work. Basically it doesn't sort on clicking columns.

        var grid;

        var columns = [
        {id:"title", name:"Title", field:"title", sortable: true},
        {id:"duration", name:"Duration", field:"duration", sortable: true},
        {id:"%", name:"% Complete", field:"percentComplete", sortable: true},
        {id:"start", name:"Start", field:"start", sortable: true},
        {id:"finish", name:"Finish", field:"finish", sortable: true},
        {id:"effort-driven", name:"Effort Driven", field:"effortDriven", sortable: true}
        ];

        var options = {
            enableCellNavigation: true,
            enableColumnReorder: false
        };

        $(function() {
            var data = [];
            for (var i = 0; i < 500; i++) {
                data[i] = {
                    id: i,
                    title: "Task " + i,
                    duration: "5 days",
                    percentComplete: Math.round(Math.random() * 100),
                    start: "01/01/2009",
                    finish: "01/05/2009",
                    effortDriven: (i % 5 == 0)
                };
            }

            var dataView = new Slick.Data.DataView();

            grid = new Slick.Grid("#myGrid", dataView, columns, options);
            function comparer(a,b) {
                var x = a[sortcol], y = b[sortcol];
                return (x == y ? 0 : (x > y ? 1 : -1));
            }

            var sortcol = "json_number";
            var sortdir = 1;
            grid.onSort.subscribe(function(e, args) {
                sortdir = args.sortAsc ? 1 : -1;
                sortcol = args.sortCol.field;

                // using native sort with comparer
                // preferred method but can be very slow in IE with huge datasets
                dataView.sort(comparer, args.sortAsc);
            });
            dataView.beginUpdate();
            dataView.setItems(data);
            dataView.endUpdate();
            grid.invalidate();
            grid.render();

            $("#myGrid").show();
        })

Answer 1

Try adding this listener, which re-renders the grid when rows get shuffled around:

dataView.onRowsChanged.subscribe(function(e,args) {
    grid.invalidateRows(args.rows);
    grid.render();
});

Original example here: http://mleibman.github.com/SlickGrid/examples/example4-model.html