bootstrap 範行：
<div class="btn-group">
<button class="btn">Please Select From List</button>
<button class="btn dropdown-toggle" data-toggle="dropdown">
<span class="caret"></span>
</button>
<ul class="dropdown-menu" role="menu" aria-labelledby="dropdownMenu">
<li><a tabindex="-1" href="#">Item I</a></li>
<li><a tabindex="-1" href="#">Item II</a></li>
<li><a tabindex="-1" href="#">Item III</a></li>
<li class="divider"></li>
<li><a tabindex="-1" href="#">Other</a></li>
</ul>
</div>
bootstrap v3.3 官方教學：
https://getbootstrap.com/docs/3.3/components/#dropdowns
問題是，下拉式 button ，希望點選了 menu item 可以把選擇的項目，更新回顯用的元件的標題裡，官方提供的不會更新button 的title. 解法如下：
As far as i understood your issue is that you want to change the text of the button with the clicking linked text, if so you can try this one: http://jsbin.com/owuyix/4/edit
$(function(){
$(".dropdown-menu li a").click(function(){
$(".btn:first-child").text($(this).text());
$(".btn:first-child").val($(this).text());
});
});
As per your comment:
this doesn’t work for me when I have lists item <li> populated through ajax call.
so you have to delegate the event to the closest static parent with .on() jQuery method:
$(function(){
$(".dropdown-menu").on('click', 'li a', function(){
$(".btn:first-child").text($(this).text());
$(".btn:first-child").val($(this).text());
});
});
Here event is delegated to static parent $(".dropdown-menu"), although you can delegate the event to the $(document) too because it is always available.
我服用的 html:
<div class="dropdown">
<button class="btn btn-default dropdown-toggle" type="button" id="dropdownMenu1" data-toggle="dropdown" aria-haspopup="true" aria-expanded="true">
<span class="caret"></span>
</button>
<ul class="dropdown-menu" aria-labelledby="dropdownMenu1">
<li><a href="#"> </a></li>
<li><a href="#">Android</a></li>
<li><a href="#">iOS</a></li>
</ul>
</div>
我服用的 javascript:
$(function(){
$(".dropdown-menu").on('click', 'li a', function(){
$(".btn:first-child").html($(this).text()+' <span class="caret"></span>');
});
});
如果有多組 dropdown list 我是使用：
html:
<div class="dropdown">
<button class="btn btn-default dropdown-toggle" type="button" data-toggle="dropdown" id="dropdownMenu1">
<span class="caret"></span>
</button>
<ul class="dropdown-menu" id="dropdownMenu1Item">
<li><a href="#"> </a></li>
<li><a href="#">Android</a></li>
<li><a href="#">iOS</a></li>
</ul>
</div>
javascript:
$(function(){
$("#dropdownMenu2Item").on('click', 'li a', function(){
var selText = $(this).text();
$("#dropdownMenu2:first-child").html(selText+' <span class="caret"></span>');
});
});
$(function(){
$("#dropdownMenu1Item").on('click', 'li a', function(){
var selText = $(this).text();
$("#dropdownMenu1:first-child").html(selText+' <span class="caret"></span>');
});
});
相關範例：
https://www.bootply.com/64302
