Question

我在用HTML CSS和Bootstrap制成的导航栏很挣扎。我已经按照youtube上的一些教程进行操作，但是当屏幕尺寸减小到最小时，我似乎可以展开切换按钮。因为我开始一个新项目，所以我将所有这些都应用了HTML CSS和Bootstrap，并在本地目录中打开了HTML文件。请帮我！我被困了几个小时。

下面是我执行的代码：

<head>
    <meta charset="UTF-8"/>
    <meta name="viewport" content="width=device-width, initial-scale=1.0"/>
    <meta http-equiv="X-UA-Compatible" content="ie=edge"/>
    <script src="https://code.jquery.com/jquery-3.5.1.js"></script>
    <link rel="stylesheet" href="bootstrap.min.css"/>
    <link rel="stylesheet" href="title.css" />
    <title>Document</title>
</head>
<body>
   <nav class="navbar navbar-expand-md navbar-light bg-light sticky-top">
     <button class="navbar-toggler" data-toggle="collapse" data-target="#collapse_target">
       <span class="navbar-toggler-icon></span>
     </button>

     <div class="collapse navbar-collapse" id="collapse_target">
       <a class="navbar-brand>Logo</a>

       <ul class="navbar-nav">
         <li class="nav-item">
           <a class="nav-link href="#">Link 1</a>
         </li>
         <li class="nav-item">
           <a class="nav-link href="#">Link 2</a>
         </li>
         <li class="nav-item">
           <a class="nav-link href="#">Link 3</a>
         </li>
      </ul>
    </div>
   </nav>
</body>

我的结果如下：

我将获得如上所述的切换图标，但无法单击它并获得“首页”，“类别”，“关于”和“联系人”。我不知道我做错了什么地方。

谢谢您的时间。

Answer 1

您错过了JS，可以在getbootstrap.com中找到其CDN。我在下面添加了两个响应式导航栏。这些代码在getbootstrap.com中使用

<!doctype html>
<html lang="en">
  <head>
    <!-- Required meta tags -->
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">

    <!-- Bootstrap CSS -->
    <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@4.5.3/dist/css/bootstrap.min.css" integrity="sha384-TX8t27EcRE3e/ihU7zmQxVncDAy5uIKz4rEkgIXeMed4M0jlfIDPvg6uqKI2xXr2" crossorigin="anonymous">

    <title>Document</title>
  </head>
  <body>
    <nav class="navbar navbar-expand-sm navbar-dark bg-dark">
  <a class="navbar-brand" href="#">Expand at sm</a>
  <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarsExample03" aria-controls="navbarsExample03" aria-expanded="false" aria-label="Toggle navigation">
    <span class="navbar-toggler-icon"></span>
  </button>

  <div class="collapse navbar-collapse" id="navbarsExample03">
    <ul class="navbar-nav mr-auto">
      <li class="nav-item active">
        <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Link</a>
      </li>
      <li class="nav-item">
        <a class="nav-link disabled" href="#" tabindex="-1" aria-disabled="true">Disabled</a>
      </li>
      <li class="nav-item dropdown">
        <a class="nav-link dropdown-toggle" href="#" id="dropdown03" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Dropdown</a>
        <div class="dropdown-menu" aria-labelledby="dropdown03">
          <a class="dropdown-item" href="#">Action</a>
          <a class="dropdown-item" href="#">Another action</a>
          <a class="dropdown-item" href="#">Something else here</a>
        </div>
      </li>
    </ul>
    <form class="form-inline my-2 my-md-0">
      <input class="form-control" type="text" placeholder="Search">
    </form>
  </div>
</nav>

<hr class"m-5">
<nav class="navbar navbar-expand-xl navbar-dark bg-dark">
  <a class="navbar-brand" href="#">Expand at xl</a>
  <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarsExample06" aria-controls="navbarsExample06" aria-expanded="false" aria-label="Toggle navigation">
    <span class="navbar-toggler-icon"></span>
  </button>

  <div class="collapse navbar-collapse" id="navbarsExample06">
    <ul class="navbar-nav mr-auto">
      <li class="nav-item active">
        <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Link</a>
      </li>
      <li class="nav-item">
        <a class="nav-link disabled" href="#" tabindex="-1" aria-disabled="true">Disabled</a>
      </li>
      <li class="nav-item dropdown">
        <a class="nav-link dropdown-toggle" href="#" id="dropdown06" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Dropdown</a>
        <div class="dropdown-menu" aria-labelledby="dropdown06">
          <a class="dropdown-item" href="#">Action</a>
          <a class="dropdown-item" href="#">Another action</a>
          <a class="dropdown-item" href="#">Something else here</a>
        </div>
      </li>
    </ul>
    <form class="form-inline my-2 my-md-0">
      <input class="form-control" type="text" placeholder="Search">
    </form>
  </div>
</nav>
    <!-- Optional JavaScript; choose one of the two! -->

    <!-- Option 1: jQuery and Bootstrap Bundle (includes Popper) -->
    <script src="https://code.jquery.com/jquery-3.5.1.slim.min.js" integrity="sha384-DfXdz2htPH0lsSSs5nCTpuj/zy4C+OGpamoFVy38MVBnE+IbbVYUew+OrCXaRkfj" crossorigin="anonymous"></script>
    <script src="https://cdn.jsdelivr.net/npm/bootstrap@4.5.3/dist/js/bootstrap.bundle.min.js" integrity="sha384-ho+j7jyWK8fNQe+A12Hb8AhRq26LrZ/JpcUGGOn+Y7RsweNrtN/tE3MoK7ZeZDyx" crossorigin="anonymous"></script>

    
    <script src="https://code.jquery.com/jquery-3.5.1.slim.min.js" integrity="sha384-DfXdz2htPH0lsSSs5nCTpuj/zy4C+OGpamoFVy38MVBnE+IbbVYUew+OrCXaRkfj" crossorigin="anonymous"></script>
    <script src="https://cdn.jsdelivr.net/npm/popper.js@1.16.1/dist/umd/popper.min.js" integrity="sha384-9/reFTGAW83EW2RDu2S0VKaIzap3H66lZH81PoYlFhbGU+6BZp6G7niu735Sk7lN" crossorigin="anonymous"></script>
    <script src="https://cdn.jsdelivr.net/npm/bootstrap@4.5.3/dist/js/bootstrap.min.js" integrity="sha384-w1Q4orYjBQndcko6MimVbzY0tgp4pWB4lZ7lr30WKz0vr/aWKhXdBNmNb5D92v7s" crossorigin="anonymous"></script>

  </body>
</html>

Answer 2

引导程序需要JavaScript才能正常运行。您应该添加Bootstrap所需的脚本。来源：https://getbootstrap.com/docs/4.5/getting-started/introduction/#js

<script src="https://code.jquery.com/jquery-3.5.1.slim.min.js" integrity="sha384-DfXdz2htPH0lsSSs5nCTpuj/zy4C+OGpamoFVy38MVBnE+IbbVYUew+OrCXaRkfj" crossorigin="anonymous"></script>
<script src="https://cdn.jsdelivr.net/npm/bootstrap@4.5.3/dist/js/bootstrap.bundle.min.js" integrity="sha384-ho+j7jyWK8fNQe+A12Hb8AhRq26LrZ/JpcUGGOn+Y7RsweNrtN/tE3MoK7ZeZDyx" crossorigin="anonymous"></script>

Answer 3

您在Javascript中遇到的问题。请在代码中添加Boostrap JS。
您可以在页面上运行此代码。

示例：

<html>
<head>
  <meta charset="UTF-8"/>
  <meta name="viewport" content="width=device-width, initial-scale=1.0"/>
  <meta http-equiv="X-UA-Compatible" content="ie=edge"/>
  <script src="https://code.jquery.com/jquery-3.5.1.js"></script>
  <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta.2/css/bootstrap.min.css"/>
  <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.3/umd/popper.min.js"></script>
  <script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta.2/js/bootstrap.min.js"></script>
  <title>Document</title>
</head>
<body>
  <nav class="navbar navbar-expand-lg navbar-light bg-light container">
    <a class="navbar-brand" href="#">Boostrap</a>
    <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarSupportedContent" aria-controls="navbarSupportedContent" aria-expanded="false" aria-label="Toggle navigation">
      <span class="navbar-toggler-icon"></span>
    </button>
  
    <div class="collapse navbar-collapse" id="navbarSupportedContent">
      <ul class="navbar-nav mr-auto">
        <li class="nav-item active">
          <a class="nav-link" href="#">Now<span class="sr-only">(current)</span></a>
        </li>
        <li class="nav-item">
          <a class="nav-link" href="#">Can</a>
        </li>
        <li class="nav-item">
          <a class="nav-link" href="#">Use</a>
        </li>
        <li class="nav-item dropdown">
          <a class="nav-link dropdown-toggle" href="#" id="navbarDropdown" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
            Dropdown
          </a>
          <div class="dropdown-menu" aria-labelledby="navbarDropdown">
            <a class="dropdown-item" href="#">Action</a>
            <a class="dropdown-item" href="#">Another action</a>
            <div class="dropdown-divider"></div>
            <a class="dropdown-item" href="#">Something else here</a>
          </div>
        </li>
        <li class="nav-item">
          <a class="nav-link disabled" href="#">Donate Me</a>
        </li>
      </ul>
      <form class="form-inline my-2 my-lg-0">
        <input class="form-control mr-sm-2" type="search" placeholder="Search" aria-label="Search">
        <button class="btn btn-outline-success my-2 my-sm-0" type="submit">Searching</button>
      </form>
    </div>
  </nav>
</body>
</html>

Answer 4

您似乎在按钮标记中缺少“类型：按钮”，如下所示：

<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#collapse_target">

Bootstrap导航栏切换不起作用（展开）

4 个答案: