我遇到了最新的 jQuery 组合框的问题。用例如下所述。
- 我在组合框中输入一些内容，这会显示所有匹配选项，然后我选择其中一个匹配选项。这会将组合框文本设置为所选项目的文本。
- 现在，我将焦点移出组合框，然后回到组合框并删除所有文本，但不选择其他项目。即使所选值存在，组合框仍显示空白文本。这对我来说似乎不是很直观，因为空白文本应该意味着没有选择任何选项。
可以在此处找到说明此问题的视频：http: //screencast.com/t/QLUtZYsL2
这就是我在上述用例中的目标： 我想确保万一用户以某种方式删除组合框文本，然后在离开组合框时，文本将恢复为所选项目的文本。
带有 jQuery 组合框的示例 html 页面如下所示。
<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>jQuery UI Example Page</title>
<link type="text/css" href="css/cupertino/jquery-ui-1.8.21.custom.css" rel="stylesheet" />
<script type="text/javascript" src="js/jquery-1.7.2.min.js"></script>
<script type="text/javascript" src="js/jquery-ui-1.8.21.custom.min.js"></script>
<script type="text/javascript" src="http://jzaefferer.github.com/jquery-validation/jquery.validate.js"></script>
<style>
.ui-combobox {
position: relative;
display: inline-block;
}
.ui-combobox-toggle {
position: absolute;
top: 0;
bottom: 0;
margin-left: -1px;
padding: 0;
/* adjust styles for IE 6/7 */
*height: 1.7em;
*top: 0.1em;
}
.ui-combobox-input {
margin: 0;
padding: 0.3em;
}
</style>
<script type="text/javascript">
(function ($) {
$.widget("ui.combobox", {
_create: function () {
var input,
self = this,
select = this.element.hide(),
selected = select.children(":selected"),
value = selected.val() ? selected.text() : "",
wrapper = this.wrapper = $("<span>")
.addClass("ui-combobox")
.insertAfter(select);
input = $("<input>")
.appendTo(wrapper)
.val(value)
.addClass("ui-state-default ui-combobox-input")
.autocomplete({
delay: 0,
minLength: 0,
source: function (request, response) {
var matcher = new RegExp($.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
});
},
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;
}
});
if (!valid) {
// 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 ui-corner-left");
input.data("autocomplete")._renderItem = function (ul, item) {
return $("<li></li>")
.data("item.autocomplete", item)
.append("<a>" + item.label + "</a>")
.appendTo(ul);
};
$("<a>")
.attr("tabIndex", -1)
.attr("title", "Show All Items")
.appendTo(wrapper)
.button({
icons: {
primary: "ui-icon-triangle-1-s"
},
text: false
})
.removeClass("ui-corner-all")
.addClass("ui-corner-right ui-combobox-toggle")
.click(function () {
// 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.wrapper.remove();
this.element.show();
$.Widget.prototype.destroy.call(this);
}
});
})(jQuery);
$(function () {
$("#combobox").combobox();
$("#toggle").click(function () {
$("#combobox").toggle();
});
});
</script>
</head>
<body>
<div class="demo">
<div class="ui-widget">
<label>
Your preferred programming language:
</label>
<select id="combobox">
<option value="">Select one...</option>
<option value="ActionScript">ActionScript</option>
<option value="AppleScript">AppleScript</option>
<option value="Asp">Asp</option>
<option value="BASIC">BASIC</option>
<option value="C">C</option>
<option value="C++">C++</option>
<option value="Clojure">Clojure</option>
<option value="COBOL">COBOL</option>
<option value="ColdFusion">ColdFusion</option>
<option value="Erlang">Erlang</option>
<option value="Fortran">Fortran</option>
<option value="Groovy">Groovy</option>
<option value="Haskell">Haskell</option>
<option value="Java">Java</option>
<option value="JavaScript">JavaScript</option>
<option value="Lisp">Lisp</option>
<option value="Perl">Perl</option>
<option value="PHP">PHP</option>
<option value="Python">Python</option>
<option value="Ruby">Ruby</option>
<option value="Scala">Scala</option>
<option value="Scheme">Scheme</option>
</select>
</div>
<button id="toggle">
Show underlying select</button>
</div>
<!-- End demo -->
</body>
</html>