Question

我将here中的代码粘贴到了我的Web应用程序中。除了 Service C下拉子菜单。我看不到Service C1 ... Service C5。

<ul class="nav navbar-nav">
        <li class="active"><a href="#">Home</a></li>
        <li><a href="#about">About</a></li>
        <li class="dropdown">
            <a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="true"> <span class="nav-label">Services</span> <span class="caret"></span></a>
            <ul class="dropdown-menu">
                <li><a href="#">Service A</a></li>
                <li><a href="#">Service B</a></li>
                <li class="dropdown-submenu">
                    <a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false"> <span class="nav-label">Service C</span><span class="caret"></span></a>
                    <ul class="dropdown-menu">
                        <li><a href="#">Service C1</a></li>
                        <li><a href="#">Service C2</a></li>
                        <li><a href="#">Service C3</a></li>
                        <li><a href="#">Service C4</a></li>
                        <li><a href="#">Service C5</a></li>
                    </ul>
                </li>
            </ul>
        </li>
    </ul>

页面现在写：

The support for sub-menu was disabled in latest version of bootstrap. The option can be re-enabled by including a small CSS.

您知道所需的CSS及其放置位置吗？

我正在使用bootstrap 3.3.7，并且不想更改此版本。

Answer 1

我做了一些更改看到它

$(document).ready(function(){
  $('.dropdown-submenu a.test').on("click", function(e){
    $(this).next('ul').toggle();
    e.stopPropagation();
    e.preventDefault();
  });
});

<!DOCTYPE html>
<html>
<head>
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.0/css/bootstrap.min.css">
  <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.4.1/jquery.min.js"></script>
  <script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.0/js/bootstrap.min.js"></script>
<style>
.dropdown-submenu {
  position: relative;
}

.dropdown-submenu .dropdown-menu {
  top: 0;
  left: 100%;
  margin-top: -1px;
}
</style>
</head>
<body>
   
<div class="container">                                      
 <ul class="nav navbar-nav">
        <li class="active"><a href="#">Home</a></li>
        <li><a href="#about">About</a></li>
        <li class="dropdown">
            <a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="true"> <span class="nav-label">Services</span> <span class="caret"></span></a>
            <ul class="dropdown-menu">
                <li><a href="#">Service A</a></li>
                <li><a href="#">Service B</a></li>
                <li class="dropdown-submenu">
                    <a class="test" href="#">Service C <span class="caret"></span></a>
                    <ul class="dropdown-menu">
                        <li><a href="#">Service C1</a></li>
                        <li><a href="#">Service C2</a></li>
                        <li><a href="#">Service C3</a></li>
                        <li><a href="#">Service C4</a></li>
                        <li><a href="#">Service C5</a></li>
                    </ul>
                </li>
            </ul>
        </li>
    </ul>
</div>



</body>
</html>

Answer 2

如您在bootstrap css file中所见，

.dropdown-menu具有display:none属性。您可以像这样轻松添加display:block类：

$(document).ready(function(){
  $('.dropdown-toggle').on("click", function(e){
    $(this).next('.dropdown-menu').toggleClass("opened");
  });
});

.opened {
  display: block !important;
}

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.4.1/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>

<ul class="nav navbar-nav">
  <li class="active"><a href="#">Home</a></li>
  <li><a href="#about">About</a></li>
  <li class="dropdown">
    <a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="true"> <span class="nav-label">Services</span> <span class="caret"></span></a>
    <ul class="dropdown-menu">
      <li><a href="#">Service A</a></li>
      <li><a href="#">Service B</a></li>
      <li class="dropdown-submenu">
        <a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false"> <span class="nav-label">Service C</span><span class="caret"></span></a>
        <ul class="dropdown-menu">
          <li><a href="#">Service C1</a></li>
          <li><a href="#">Service C2</a></li>
          <li><a href="#">Service C3</a></li>
          <li><a href="#">Service C4</a></li>
          <li><a href="#">Service C5</a></li>
        </ul>
      </li>
    </ul>
  </li>
</ul>

bootstrap dropdown 3.3.7子菜单不会扩展

2 个答案: