Bootstrap 4 Dropdowns Tutorial

Dropdown menu is a graphical control element like a list box that allows the user to choose one value from a predefined list. It is a toggleable menu.

Bootstrap provides the following classes to create a dropdown.
.dropdown: class is used to create a dropdown menu.
.dropdown-toggle: class is used to make dropdown toggleable.
.caret: class is used to create a caret arrow icon.
.dropdown-menu: class is used with div element to actually build the dropdown menu.
.dropdown-item: class is used to each element (links or buttons) inside the dropdown menu.

Bootstrap 4 Dropdowns Example:

<!DOCTYPE html>
<html>
<head>
  <title>Bootstrap Dropdowns Example</title>
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css">
  <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
  <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.9/umd/popper.min.js"></script>
  <script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js"></script>
</head>
<body>
 
<div class="container">
  <h2>Bootstrap Dropdowns Example</h2>  
  <div class="dropdown">
    <button type="button" class="btn btn-primary dropdown-toggle" data-toggle="dropdown">
      Tutorial
    </button>
    <div class="dropdown-menu">
      <a class="dropdown-item" href="#">Java</a>
      <a class="dropdown-item" href="#">CSS</a>
      <a class="dropdown-item" href="#">HTML</a>
    </div>
  </div>
</div>
 
</body>
</html>

Output:


Bootstrap 4 Dropdowns Divider

The .dropdown-divider class is used to separate links inside the dropdown menu with a thin horizontal border.

Bootstrap 4 Dropdowns Divider Example:

<!DOCTYPE html>
<html>
<head>
  <title>Bootstrap 4 Example</title>
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css">
  <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
  <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.9/umd/popper.min.js"></script>
  <script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js"></script>
</head>
<body>
 
<div class="container">
  <h2>Bootstrap 4 Dropdowns Example</h2>
  <div class="dropdown">
    <button type="button" class="btn btn-primary dropdown-toggle" data-toggle="dropdown">
      Tutorial
    </button>
    <div class="dropdown-menu">
      <a class="dropdown-item" href="#">Java</a>
      <a class="dropdown-item" href="#">SQL</a>
      <a class="dropdown-item" href="#">HTML</a>
      <div class="dropdown-divider"></div>
      <a class="dropdown-item" href="#">CSS</a>
    </div>
  </div>
</div>
 
</body>
</html>

Output:


Bootstrap 4 Dropdowns Position

Bootstrap Dropdown position is in left by-default. To right-align the dropdown we can use .dropdown-menu-right class to the element with .dropdown-menu.

Bootstrap 4 Dropdowns Position Example:

<!DOCTYPE html>
<html>
<head>
  <title>Bootstrap 4 Example</title>
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css">
  <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
  <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.9/umd/popper.min.js"></script>
  <script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js"></script>
</head>
<body>
 
<div class="container">
  <h2>Bootstrap Dropdowns Example</h2>
  <div class="dropdown">
    <button type="button" class="btn btn-primary dropdown-toggle" data-toggle="dropdown">
      Tutorial
    </button>
    <div class="dropdown-menu dropdown-menu-right">
      <a class="dropdown-item" href="#">Java</a>
      <a class="dropdown-item" href="#">HTML</a>
      <a class="dropdown-item" href="#">CSS</a>
    </div>
  </div>
</div>
 
</body>
</html>

Output:


Bootstrap 4 Dropdowns Active and Disable

Bootstrap provides the following classes to disable and active dropdown items.
.active: class is used to highlight a specific dropdown item.
.disabled: class is used to disable a specific dropdown item.

Bootstrap 4 Dropdowns Active and Disable Example:

<!DOCTYPE html>
<html>
<head>
  <title>Bootstrap 4 Example</title>
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css">
  <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
  <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.9/umd/popper.min.js"></script>
  <script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js"></script>
</head>
<body>
 
<div class="container">
  <h2>Bootstrap 4 Dropdowns Example</h2>
  <div class="dropdown">
    <button type="button" class="btn btn-primary dropdown-toggle" data-toggle="dropdown">
      Tutorial
    </button>
    <div class="dropdown-menu">
      <a class="dropdown-item" href="#">Java</a>
      <a class="dropdown-item active" href="#">HTML</a>
      <a class="dropdown-item disabled" href="#">CSS</a>
    </div>
  </div>
</div>
 
</body>
</html>

Output:


Bootstrap 4 Dropup

The .dropup class is used to expand dropdown menu upwards instead of downwards

Bootstrap 4 Dropup Example:

<!DOCTYPE html>
<html>
<head>
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.1/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/3.4.1/js/bootstrap.min.js"></script>
</head>
<body>
 
<div class="container">
  <h2>Dropdowns</h2>
  <div class="dropup">
    <button class="btn btn-default dropdown-toggle" type="button" data-toggle="dropdown">Tutorial
    <span class="caret"></span></button>
    <ul class="dropdown-menu">
      <li><a href="#">SQL</a></li>
      <li><a href="#">Java</a></li>
    </ul>
  </div>
</div>
 
</body>
</html>

Output:


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