滚动时jQuery自动完成框保持打开并处于相同位置

Question

当自动完成文本框展开，并且用户滚动浏览器页面时，该框保持在相同的位置并且不会消失。如果它保持在同一个位置，我可以打开它，但我不明白为什么它会保持在滚动的同一个位置。

function ($) {
    $.widget("ui.combobox", {
        _create: function () {
            var self = this,
                select = this.element.hide(),
                selected = select.children(":selected"),
                value = selected.val() ? selected.text() : "";
            var input = this.input = $("<input id='innertextbox'>")
                .insertAfter(select)
                .autocomplete({
                    delay: 0,
                    minLength: 0,
                    source: function (request, response) {
                        var matcher = new RegExp($.ui.autocomplete.escapeRegex(request.term), "i");
                        response(select.children("option").map(function () {
                            var text = $(this).text();
                            if (this.value && (!request.term || matcher.test(text)))
                                return {
                                    label: text.replace(
                new RegExp(
                "(?![^&;]+;)(?!<[^<>]*)(" +
                $.ui.autocomplete.escapeRegex(request.term) +
                ")(?![^<>]*>)(?![^&;]+;)", "gi"
                ), "<strong>$1</strong>"),
                                    value: text,
                                    option: this
                                };
                        }));
                    },
                    select: function (event, ui) {
                        ui.item.option.selected = true;
                        self._trigger("selected", event, {
                            item: ui.item.option
                        });
                        if (jQuery(ui.item.option).hasClass('_self'))
                            window.location.href = ui.item.option.value;
                        else
                            window.open(ui.item.option.value,'_newtab');
                    },
                    change: function (event, ui) {
                        if (!ui.item) {
                            var matcher = new RegExp("^" + $.ui.autocomplete.escapeRegex($(this).val()) + "$", "i"),
                valid = false;
                            select.children("option").each(function () {
                                if ($(this).text().match(matcher)) {
                                    this.selected = valid = true;
                                    return false;
                                }
                            }); var innerBoxValue = $("#innertextbox").val(); 

                            if (!valid && innerBoxValue != "Daily Needs...")  {
                                // remove invalid value, as it didn't match anything
                                $(this).val("");
                                select.val("");
                                input.data("autocomplete").term = "";
                                return false;
                            }
                        }
                    }
                })

                .addClass("ui-widget ui-widget-content");

            input.data("autocomplete")._renderItem = function (ul, item) {
                return $("<li></li>")
                .data("item.autocomplete", item)
                .append("<a>" + item.label + "</a>")
                .appendTo(ul);
            };
            this.button = $("<button type='button' id='dailyNeedsButton'>&nbsp;</button>")
                .attr("tabIndex", -1)
                .attr("title", "Show All Items")
                .insertAfter(input)
                .button({
                    icons: {
                        primary: "ui-icon-triangle-1-s"
                    },
                    text: false
                })
                .removeClass("ui-corner-all")
                .addClass("ui-button-icon")
                .click(function () {
        jQuery("#innertextbox").val("");
                    // close if already visible
                    if (input.autocomplete("widget").is(":visible")) {
                        input.autocomplete("close");
                        return;
                    }
                    // work around a bug (likely same cause as #5265)
                    $(this).blur();
                    // pass empty string as value to search for, displaying all results
                    input.autocomplete("search", "");
                    input.focus();
                });

        },
        destroy: function () {
            this.input.remove();
            this.button.remove();
            this.element.show();
            $.Widget.prototype.destroy.call(this);
        }
    });
})(jQuery);

jQuery(document).ready(function () {

    jQuery("#dailyNeedsSelect").combobox();
    jQuery("#innertextbox").blur(function () {
        jQuery("#innertextbox").val("Daily Needs...");
    });
    jQuery("#innertextbox").val("Daily Needs...");
    jQuery(".ui-autocomplete").position({ my: "right top", at: "right bottom", of: jQuery("#innertextbox"), collision: "flip flip" }); 

    jQuery("#dailyNeedsButton").blur(function () { jQuery("#innertextbox").val("Daily Needs..."); });
    jQuery("#innertextbox").focus(function () { if (jQuery("#innertextbox").val() == "Daily Needs...") jQuery("#innertextbox").val(""); });

    jQuery("#innertextbox").bind("click", function () {
        jQuery("#innertextbox").val("");
    });
});

Answer 1

已通过为自动完成方法添加 appendTo 选项来解决此问题：

http://docs.jquery.com/UI/Autocomplete#option-appendTo