jquery - 在焦点事件上显示 jquery ui 自动完成列表

Question

这是我的代码，有什么问题吗？它似乎没有在焦点上显示列表，我仍然需要按一个键才能显示列表

<link media="all" type="text/css" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.6/themes/smoothness/jquery-ui.css" rel="stylesheet"/>
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.3/jquery.min.js"></script>
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.6/jquery-ui.min.js"></script>

<script type="text/javascript">
    $(function() {
        $('#id').autocomplete({
            source: ["ActionScript",
                        "AppleScript",
                        "Asp",
                        "BASIC",
                        "C",
                        "C++",
                        "Clojure",
                        "COBOL",
                        "ColdFusion",
                        "Erlang",
                        "Fortran",
                        "Groovy",
                        "Haskell",
                        "Java",
                        "JavaScript",
                        "Lisp",
                        "Perl",
                        "PHP",
                        "Python",
                        "Ruby",
                        "Scala",
                        "Scheme"
                    ],
            minLength: 0
        });
    }).focus(function(){            
            $(this).trigger('keydown.autocomplete');
    });
</script>


<input type="text" id="id">

Answer 1

焦点时直接调用默认值的搜索方法。

http://jsfiddle.net/steelywing/ubugC/

$("input").autocomplete({
    source: ["Apple", "Boy", "Cat"],
    minLength: 0,
}).focus(function () {
    $(this).autocomplete("search");
});