Question

我发现我的下拉菜单（HOME CCTV）无效。任何帮助都可以得到赞赏。是新手。下拉链接非常有用。

     <nav class="navbar navbar-expand-lg">
        <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarNavDropdown" aria-controls="navbarNavDropdown" aria-expanded="false" aria-label="Toggle navigation">
            <span class="navbar-toggler-icon">
       <div class="bar1"></div>
  <div class="bar2"></div>
  <div class="bar3"></div>
    </span>
        </button>
        <div class="collapse navbar-collapse" id="navbarNavDropdown">
            <ul class="navbar-nav">
                <li class="nav-item active">
                    <a class="nav-link" href="index.html">Home <span class="sr-only">(current)</span></a>
                </li>
                <li class="nav-item dropdown">
                    <a class="nav-link dropdown-toggle" href="home-cctv-intro.html" id="navbarDropdownMenuLink" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
          Home CCTV
        </a>
                    <div class="dropdown-menu" aria-labelledby="navbarDropdownMenuLink">
                        <a class="dropdown-item" href="home-cctv-intro.html">Introduction</a>
                        <a class="dropdown-item" href="home-cctv-footage.html">Footage</a>
                        <a class="dropdown-item" href="home-cctv-cost.html">Costs</a>
                        <a class="dropdown-item" href="home-cctv-quote.html">Get a Quote</a>
                    </div>
                </li>


                <!-- jQuery first, then Popper.js, then Bootstrap JS -->
    <script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" crossorigin="anonymous"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.3/umd/popper.min.js" crossorigin="anonymous"></script>
    <script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta.2/js/bootstrap.min.js" crossorigin="anonymous"></script>

用于下拉悬停链接的JS文件

$('body').on('mouseenter mouseleave','.dropdown',function(e){
  var _d=$(e.target).closest('.dropdown');_d.addClass('show');
  setTimeout(function(){
    _d[_d.is(':hover')?'addClass':'removeClass']('show');
  },300);
});

Answer 1

<!DOCTYPE html>
<html lang="en">
<head>
  <title>Bootstrap Example</title>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta.2/css/bootstrap.min.css">
  <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>
<script type="text/javascript">
    $(document).ready(function(){
     $("li.dropdown").hover(function(){
      $(this).toggleClass("show");
       $('.dropdown-menu').toggleClass("show");

      $('.nav-link.dropdown-toggle').attr('aria-expanded' , 'true');
    }); 
});
</script>
</head>
<body>


    <nav class="navbar navbar-expand-lg">
        <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarNavDropdown" aria-controls="navbarNavDropdown" aria-expanded="false" aria-label="Toggle navigation">
            <span class="navbar-toggler-icon">
       <div class="bar1"></div>
  <div class="bar2"></div>
  <div class="bar3"></div>
    </span>
        </button>
        <div class="collapse navbar-collapse" id="navbarNavDropdown">
            <ul class="navbar-nav">
                <li class="nav-item active">
                    <a class="nav-link" href="index.html">Home <span class="sr-only">(current)</span></a>
                </li>
                <li class="nav-item dropdown">
                    <a class="nav-link dropdown-toggle" href="home-cctv-intro.html" id="navbarDropdownMenuLink" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
          Home CCTV
                    </a>
                    <div class="dropdown-menu" aria-labelledby="navbarDropdownMenuLink">
                        <a class="dropdown-item" href="home-cctv-intro.html">Introduction</a>
                        <a class="dropdown-item" href="home-cctv-footage.html">Footage</a>
                        <a class="dropdown-item" href="home-cctv-cost.html">Costs</a>
                        <a class="dropdown-item" href="home-cctv-quote.html">Get a Quote</a>
                    </div>
                </li>
</ul>
</div>
</nav>

                <!-- jQuery first, then Popper.js, then Bootstrap JS -->


  <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.6/umd/popper.min.js"></script>
  <script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta.2/js/bootstrap.min.js"></script>
    </body>
</html>

Boostrap下拉菜单无法正常工作

1 个答案: