Extend jQuery UI

gistfile1.txt

// add some functions (or override some functions) 
// e.g. $(selector).autocomplete("doMore", data);

$.widget("ui.autocomplete", $.ui.autocomplete, {

    doMore: function (data) {
        // this = autocomplete object
        // this.element = auto complete input element
    },

    overRideBlur: function() {
        this._on(this.element, {
            blur: function (event) {
                // the standard blur code
                if (this.cancelBlur) {
                    delete this.cancelBlur;
                    return;
                }

                clearTimeout(this.searching);
                this.close(event);
                this._change(event);

                // raise an extra event
                $(this.element).trigger("autocompleteblur");
            }
        }); 
    }

});

override a built in function

$.widget("ui.autocomplete", $.extend({}, $.ui.autocomplete.prototype, {

    _search: function (value) {
        this.pending++;
        this.element.addClass("ui-autocomplete-loading");
        this.cancelSearch = false;

        this.source({ term: value }, this._response());
    }

}));