如何将knockout observable与jquery barrating插件连接？

<div id="rating" data-bind="barrating: rating"></div>

var ViewModel = function() {
    this.rating = ko.observable(0);
};

ko.applyBindings(new ViewModel());

ko.bindingHandlers.barrating = {
    init: function(element, valueAccessor) {
        $(element).barrating({
            // 配置barrating插件的选项
            // 例如：theme: 'fontawesome'
        });

        // 当评分发生变化时，更新knockout observable的值
        $(element).on('change', function() {
            var value = $(element).val();
            valueAccessor()(value);
        });
    },
    update: function(element, valueAccessor) {
        // 当knockout observable的值发生变化时，更新barrating插件的评分
        var value = ko.unwrap(valueAccessor());
        $(element).barrating('set', value);
    }
};