ColVis event on click not working

jimboy

var table = $("#tableName").DataTable();
    var colvis = new $.fn.dataTable.ColVis(table, {
        "fnStateChange": function (iColumn, bVisible) {
                    alert('NOT WORKING...');
        }
    });
    $(colvis.button()).insertBefore("div.class");

Why my code above is not working? To click the colvis button and fire an event to handle dom manipulation.