Question

我正在尝试学习使用Bootstrap 4制作导航栏，当我在导航栏上创建切换按钮时，它不会像互联网上的任何教程一样隐藏。我希望它在PC上打开网络时隐藏，而在移动应用程序上打开时显示。请帮助我。

    <!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
<title>Best music buy website</title>
<link rel="stylesheet" type="text/css" href="css/style.css">
<script src="https://code.jquery.com/jquery-3.4.1.slim.min.js" integrity="sha384-J6qa4849blE2+poT4WnyKhv5vZF5SrPo0iEjwBvKU7imGFAV0wwj1yYfoRSJoZ+n" crossorigin="anonymous"></script>
<script src="https://cdn.jsdelivr.net/npm/popper.js@1.16.0/dist/umd/popper.min.js" integrity="sha384-Q6E9RHvbIyZFJoft+2mJbHaEWldlvI9IOYy5n3zV9zzTtmI3UksdQRVvoxMfooAo" crossorigin="anonymous"></script>
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.4.0/js/bootstrap.min.js" integrity="sha384-3qaqj0lc6sV/qpzrc1N5DC6i1VRn/HyX4qdPaiEFbn54VjQBEU341pvjz7Dv3n6P" crossorigin="anonymous"></script>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.0/css/bootstrap.min.css">

<link href="css/all.css" rel="stylesheet">


</head>
<body>
   <nav class="navbar navbar-expand-md navbar-default navbar-fixed-top  ">
    <div class="container-fluid">

     <div class="navbar-header">
      <a href="#" class="navbar-brand">MP3</a> 
      <button type="button" data-toggle="collapse" data-target="#navbar">
      <span class="glyphicon glyphicon-align-justify"></span>
    </button>
    </div>

     <div class="collapse navbar-collapse" id="navbar">
     <ul class="nav navbar-nav" >
       <li class="nav-item"><a class="nav-link" href="#">HOME</a></li>
       <li class="dropdown"><a class="dropdown-toggle" data-toggle="dropdown" href="#" >The Loai</a>
        <ul class="dropdown-menu">
          <li class="nav-item"><a href="#">Buon</a></li>
          <li class="nav-item"><a href="#">Vui</a></li>
          <li class="nav-item"><a class="nav-link" href="#">Giut Giut</a></li>

        </ul>
       </li>
       <li class="nav-item"><a class="nav-link" href="#">Top100</a></li>
       <li class="nav-item"><a class="nav-link" href="#">Chu De</a></li>
       <li class="nav-item"><a class="nav-link" href="#">Album</a></li>
       <li class="nav-item"><a class="nav-link" href="#">Nghe Si</a></li>
     </ul>

     <ul class="nav navbar-nav navbar-right">
       <li class="dropdown"><a class="dropdown-toggle" data-toggle="dropdown" href="#"><span class="glyphicon glyphicon-user"></span> Tai Khoan</a>
        <ul class="dropdown-menu">
          <li><a href="#">Dang Ki</a></li>
          <li><a href="#">Dang Nhap</a></li>
        </ul>
       </li>
      </ul>
   </div>
 </div>
   </nav>
<br>

</body>
</html>

Answer 1

Please insert <style> tag in head and following css:
<style>
.mobile{display: none !important;}
@media screen and (min-width: 600px) {
    .mobile{display: block !important;}
}
</style>

In body Give class "mobile" to button:

<button type="button" data-toggle="collapse" data-target="#navbar" class="mobile">
      <span class="glyphicon glyphicon-align-justify"></span>
</button>

whenever screen resolution is less than 600px, it will displayed

Answer 2

** you can do this with css please add this css in you main css file working fine now.

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
<title>Best music buy website</title>
<link rel="stylesheet" type="text/css" href="css/style.css">
<script src="https://code.jquery.com/jquery-3.4.1.slim.min.js" integrity="sha384-J6qa4849blE2+poT4WnyKhv5vZF5SrPo0iEjwBvKU7imGFAV0wwj1yYfoRSJoZ+n" crossorigin="anonymous"></script>
<script src="https://cdn.jsdelivr.net/npm/popper.js@1.16.0/dist/umd/popper.min.js" integrity="sha384-Q6E9RHvbIyZFJoft+2mJbHaEWldlvI9IOYy5n3zV9zzTtmI3UksdQRVvoxMfooAo" crossorigin="anonymous"></script>
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.4.0/js/bootstrap.min.js" integrity="sha384-3qaqj0lc6sV/qpzrc1N5DC6i1VRn/HyX4qdPaiEFbn54VjQBEU341pvjz7Dv3n6P" crossorigin="anonymous"></script>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.0/css/bootstrap.min.css">
<link href="css/all.css" rel="stylesheet">
<style>
.mobile-only{display: none !important;}
@media screen and (max-width: 600px) {
	.mobile-only{display: block !important;}
}
</style>

</head>
<body>
   <nav class="navbar navbar-expand-md navbar-default navbar-fixed-top  ">
    <div class="container-fluid">

     <div class="navbar-header">
      <a href="#" class="navbar-brand">MP3</a> 
      <button type="button" data-toggle="collapse" data-target="#navbar" class="mobile-only">
      <span class="glyphicon glyphicon-align-justify"></span>
    </button>
    </div>

     <div class="collapse navbar-collapse" id="navbar">
     <ul class="nav navbar-nav" >
       <li class="nav-item"><a class="nav-link" href="#">HOME</a></li>
       <li class="dropdown"><a class="dropdown-toggle" data-toggle="dropdown" href="#" >The Loai</a>
        <ul class="dropdown-menu">
          <li class="nav-item"><a href="#">Buon</a></li>
          <li class="nav-item"><a href="#">Vui</a></li>
          <li class="nav-item"><a class="nav-link" href="#">Giut Giut</a></li>

        </ul>
       </li>
       <li class="nav-item"><a class="nav-link" href="#">Top100</a></li>
       <li class="nav-item"><a class="nav-link" href="#">Chu De</a></li>
       <li class="nav-item"><a class="nav-link" href="#">Album</a></li>
       <li class="nav-item"><a class="nav-link" href="#">Nghe Si</a></li>
     </ul>

     <ul class="nav navbar-nav navbar-right">
       <li class="dropdown"><a class="dropdown-toggle" data-toggle="dropdown" href="#"><span class="glyphicon glyphicon-user"></span> Tai Khoan</a>
        <ul class="dropdown-menu">
          <li><a href="#">Dang Ki</a></li>
          <li><a href="#">Dang Nhap</a></li>
        </ul>
       </li>
      </ul>
   </div>
 </div>
   </nav>
<br>

</body>
</html>

如何在Bootstrap 4中隐藏切换按钮

2 个答案: