Dropdowns

Overview

Dropdowns are toggleable, contextual overlays for displaying lists of links and more. They’re made interactive with the included Boosted dropdown JavaScript plugin. They’re toggled by clicking, not by hovering; this is an intentional design decision.

Dropdowns are built on a third party library, Popper, which provides dynamic positioning and viewport detection. Be sure to include popper.min.js before Boosted’s JavaScript or use boosted.bundle.min.js / boosted.bundle.js which contains Popper. Popper isn’t used to position dropdowns in navbars though as dynamic positioning isn’t required.

Accessibility

The WAI ARIA standard defines an actual role="menu" widget, but this is specific to application-like menus which trigger actions or functions. ARIA menus can only contain menu items, checkbox menu items, radio button menu items, radio button groups, and sub-menus.

Boosted’s dropdowns, on the other hand, are designed to be generic and applicable to a variety of situations and markup structures. For instance, it is possible to create dropdowns that contain additional inputs and form controls, such as search fields or login forms. For this reason, Boosted does not expect (nor automatically add) any of the role and aria- attributes required for true ARIA menus. Authors will have to include these more specific attributes themselves.

However, Boosted does add built-in support for most standard keyboard menu interactions, such as the ability to move through individual .dropdown-item elements using the cursor keys and close the menu with the Esc key.

Examples

Wrap the dropdown’s toggle (your button or link) and the dropdown menu within .dropdown, or another element that declares position: relative;. Ideally, you should use a <button> element as the dropdown trigger, but the plugin will work with <a> elements as well. The examples shown here use semantic <ul> elements where appropriate, but custom markup is supported.

Single button

Any single .btn can be turned into a dropdown toggle with some markup changes. Here’s how you can put them to work with <button> elements:

<div class="dropdown">
  <button class="btn btn-dropdown dropdown-toggle" type="button" data-bs-toggle="dropdown" aria-expanded="false">
    Dropdown button
  </button>
  <ul class="dropdown-menu">
    <li><a class="dropdown-item" href="#">Action</a></li>
    <li><a class="dropdown-item" href="#">Another action</a></li>
    <li><a class="dropdown-item" href="#">Something else here</a></li>
  </ul>
</div>

While <button> is the recommended control for a dropdown toggle, there might be situations where you have to use an <a> element. If you do, we recommend adding a role="button" attribute to appropriately convey control’s purpose to assistive technologies such as screen readers.

<div class="dropdown">
  <a class="btn btn-dropdown dropdown-toggle" href="#" role="button" data-bs-toggle="dropdown" aria-expanded="false">
    Dropdown link
  </a>

  <ul class="dropdown-menu">
    <li><a class="dropdown-item" href="#">Action</a></li>
    <li><a class="dropdown-item" href="#">Another action</a></li>
    <li><a class="dropdown-item" href="#">Something else here</a></li>
  </ul>
</div>

<!-- Example single danger button -->
<div class="btn-group">
  <button type="button" class="btn btn-danger dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">
    Danger
  </button>
  <ul class="dropdown-menu">
    <li><a class="dropdown-item" href="#">Action</a></li>
    <li><a class="dropdown-item" href="#">Another action</a></li>
    <li><a class="dropdown-item" href="#">Something else here</a></li>
    <li><hr class="dropdown-divider" /></li>
    <li><a class="dropdown-item" href="#">Separated link</a></li>
  </ul>
</div>

Split button

Similarly, create split button dropdowns with virtually the same markup as single button dropdowns, but with the addition of .dropdown-toggle-split for proper spacing around the dropdown caret.

We use this extra class to reduce the horizontal padding on either side of the caret by 25% and remove the margin-left that’s added for regular button dropdowns. Those extra changes keep the caret centered in the split button and provide a more appropriately sized hit area next to the main button.

<div class="btn-group">
  <button type="button" class="btn btn-outline-secondary">Action</button>
  <button type="button" class="btn btn-outline-secondary dropdown-toggle dropdown-toggle-split" data-bs-toggle="dropdown" aria-expanded="false">
    <span class="visually-hidden">Toggle Dropdown</span>
  </button>
  <ul class="dropdown-menu">
    <li><a class="dropdown-item" href="#">Action</a></li>
    <li><a class="dropdown-item" href="#">Another action</a></li>
    <li><a class="dropdown-item" href="#">Something else here</a></li>
    <li><hr class="dropdown-divider" /></li>
    <li><a class="dropdown-item" href="#">Separated link</a></li>
  </ul>
</div>

<!-- Example split danger button -->
<div class="btn-group">
  <button type="button" class="btn btn-danger">Danger</button>
  <button type="button" class="btn btn-danger dropdown-toggle dropdown-toggle-split" data-bs-toggle="dropdown" aria-expanded="false">
    <span class="visually-hidden">Toggle Dropdown</span>
  </button>
  <ul class="dropdown-menu">
    <li><a class="dropdown-item" href="#">Action</a></li>
    <li><a class="dropdown-item" href="#">Another action</a></li>
    <li><a class="dropdown-item" href="#">Something else here</a></li>
    <li><hr class="dropdown-divider" /></li>
    <li><a class="dropdown-item" href="#">Separated link</a></li>
  </ul>
</div>

Sizing

Button dropdowns work with buttons of all sizes, including default and split dropdown buttons.

<!-- Large button groups (default and split) -->
<div class="btn-group">
  <button class="btn btn-dropdown btn-lg dropdown-toggle" type="button" data-bs-toggle="dropdown" aria-expanded="false">
    Large button
  </button>
  <ul class="dropdown-menu">
    ...
  </ul>
</div>
<div class="btn-group">
  <button class="btn btn-outline-secondary btn-lg" type="button">
    Large split button
  </button>
  <button type="button" class="btn btn-lg btn-outline-secondary dropdown-toggle dropdown-toggle-split" data-bs-toggle="dropdown" aria-expanded="false">
    <span class="visually-hidden">Toggle Dropdown</span>
  </button>
  <ul class="dropdown-menu">
    ...
  </ul>
</div>

<div class="btn-group">
  <button class="btn btn-dropdown btn-sm dropdown-toggle" type="button" data-bs-toggle="dropdown" aria-expanded="false">
    Small button
  </button>
  <ul class="dropdown-menu">
    ...
  </ul>
</div>
<div class="btn-group">
  <button class="btn btn-outline-secondary btn-sm" type="button">
    Small split button
  </button>
  <button type="button" class="btn btn-sm btn-outline-secondary dropdown-toggle dropdown-toggle-split" data-bs-toggle="dropdown" aria-expanded="false">
    <span class="visually-hidden">Toggle Dropdown</span>
  </button>
  <ul class="dropdown-menu">
    ...
  </ul>
</div>

Dark dropdowns

Deprecated in v5.3.3

Directions

Centered

Make the dropdown menu centered below the toggle with .dropdown-center on the parent element.

<div class="dropdown-center">
  <button class="btn btn-dropdown dropdown-toggle" type="button" data-bs-toggle="dropdown" aria-expanded="false">
    Centered dropdown
  </button>
  <ul class="dropdown-menu">
    <li><a class="dropdown-item" href="#">Action</a></li>
    <li><a class="dropdown-item" href="#">Action two</a></li>
    <li><a class="dropdown-item" href="#">Action three</a></li>
  </ul>
</div>

Dropup

Trigger dropdown menus above elements by adding .dropup to the parent element.

<!-- Default dropup button -->
<div class="btn-group dropup">
  <button type="button" class="btn btn-dropdown dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">
    Dropup
  </button>
  <ul class="dropdown-menu">
    <!-- Dropdown menu links -->
  </ul>
</div>

<!-- Split dropup button -->
<div class="btn-group dropup">
  <button type="button" class="btn btn-outline-secondary">
    Split dropup
  </button>
  <button type="button" class="btn btn-outline-secondary dropdown-toggle dropdown-toggle-split" data-bs-toggle="dropdown" aria-expanded="false">
    <span class="visually-hidden">Toggle Dropdown</span>
  </button>
  <ul class="dropdown-menu">
    <!-- Dropdown menu links -->
  </ul>
</div>

Dropup centered

Make the dropup menu centered above the toggle with .dropup-center on the parent element.

<div class="dropup-center dropup">
  <button class="btn btn-dropdown dropdown-toggle" type="button" data-bs-toggle="dropdown" aria-expanded="false">
    Centered dropup
  </button>
  <ul class="dropdown-menu">
    <li><a class="dropdown-item" href="#">Action</a></li>
    <li><a class="dropdown-item" href="#">Action two</a></li>
    <li><a class="dropdown-item" href="#">Action three</a></li>
  </ul>
</div>

Dropend

Trigger dropdown menus at the right of the elements by adding .dropend to the parent element.

<!-- Default dropend button -->
<div class="btn-group dropend">
  <button type="button" class="btn btn-dropdown dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">
    Dropend
  </button>
  <ul class="dropdown-menu">
    <!-- Dropdown menu links -->
  </ul>
</div>

<!-- Split dropend button -->
<div class="btn-group dropend">
  <button type="button" class="btn btn-outline-secondary">
    Split dropend
  </button>
  <button type="button" class="btn btn-outline-secondary dropdown-toggle dropdown-toggle-split" data-bs-toggle="dropdown" aria-expanded="false">
    <span class="visually-hidden">Toggle Dropend</span>
  </button>
  <ul class="dropdown-menu">
    <!-- Dropdown menu links -->
  </ul>
</div>

Dropstart

Trigger dropdown menus at the left of the elements by adding .dropstart to the parent element.

<!-- Default dropstart button -->
<div class="btn-group dropstart">
  <button type="button" class="btn btn-dropdown dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">
    Dropstart
  </button>
  <ul class="dropdown-menu">
    <!-- Dropdown menu links -->
  </ul>
</div>

<!-- Split dropstart button -->
<div class="btn-group dropstart">
  <button type="button" class="btn btn-outline-secondary dropdown-toggle dropdown-toggle-split" data-bs-toggle="dropdown" aria-expanded="false">
    <span class="visually-hidden">Toggle Dropstart</span>
  </button>
  <ul class="dropdown-menu">
    <!-- Dropdown menu links -->
  </ul>
  <button type="button" class="btn btn-outline-secondary">
    Split dropstart
  </button>
</div>

Menu items

You can use <a> or <button> elements as dropdown items.

<div class="dropdown">
  <button class="btn btn-dropdown dropdown-toggle" type="button" data-bs-toggle="dropdown" aria-expanded="false">
    Dropdown
  </button>
  <ul class="dropdown-menu">
    <li><button class="dropdown-item" type="button">Action</button></li>
    <li><button class="dropdown-item" type="button">Another action</button></li>
    <li><button class="dropdown-item" type="button">Something else here</button></li>
  </ul>
</div>

You can also create non-interactive dropdown items with .dropdown-item-text. Feel free to style further with custom CSS or text utilities.

<ul class="dropdown-menu">
  <li><span class="dropdown-item-text">Dropdown item text</span></li>
  <li><a class="dropdown-item" href="#">Action</a></li>
  <li><a class="dropdown-item" href="#">Another action</a></li>
  <li><a class="dropdown-item" href="#">Something else here</a></li>
</ul>

Active

Add .active to items in the dropdown to style them as active. To convey the active state to assistive technologies, use the aria-current attribute — using the page value for the current page, or true for the current item in a set.

<ul class="dropdown-menu">
  <li><a class="dropdown-item" href="#">Regular link</a></li>
  <li><a class="dropdown-item active" href="#" aria-current="true">Active link</a></li>
  <li><a class="dropdown-item" href="#">Another link</a></li>
</ul>

Disabled

Add .disabled to items in the dropdown to style them as disabled.

<ul class="dropdown-menu">
  <li><a class="dropdown-item" href="#">Regular link</a></li>
  <li><a class="dropdown-item disabled" aria-disabled="true">Disabled link</a></li>
  <li><a class="dropdown-item" href="#">Another link</a></li>
</ul>

Menu alignment

By default, a dropdown menu is automatically positioned 100% from the top and along the left side of its parent. You can change this with the directional .drop* classes, but you can also control them with additional modifier classes.

Add .dropdown-menu-end to a .dropdown-menu to right align the dropdown menu. Directions are mirrored when using Boosted in RTL, meaning .dropdown-menu-end will appear on the left side.

<div class="btn-group">
  <button type="button" class="btn btn-dropdown dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">
    Right-aligned menu example
  </button>
  <ul class="dropdown-menu dropdown-menu-end">
    <li><button class="dropdown-item" type="button">Action</button></li>
    <li><button class="dropdown-item" type="button">Another action</button></li>
    <li><button class="dropdown-item" type="button">Something else here</button></li>
  </ul>
</div>

Responsive alignment

If you want to use responsive alignment, disable dynamic positioning by adding the data-bs-display="static" attribute and use the responsive variation classes.

To align right the dropdown menu with the given breakpoint or larger, add .dropdown-menu{-sm|-md|-lg|-xl|-xxl}-end.

<div class="btn-group">
  <button type="button" class="btn btn-dropdown dropdown-toggle" data-bs-toggle="dropdown" data-bs-display="static" aria-expanded="false">
    Left-aligned but right aligned when large screen
  </button>
  <ul class="dropdown-menu dropdown-menu-lg-end">
    <li><button class="dropdown-item" type="button">Action</button></li>
    <li><button class="dropdown-item" type="button">Another action</button></li>
    <li><button class="dropdown-item" type="button">Something else here</button></li>
  </ul>
</div>

To align left the dropdown menu with the given breakpoint or larger, add .dropdown-menu-end and .dropdown-menu{-sm|-md|-lg|-xl|-xxl}-start.

<div class="btn-group">
  <button type="button" class="btn btn-dropdown dropdown-toggle" data-bs-toggle="dropdown" data-bs-display="static" aria-expanded="false">
    Right-aligned but left aligned when large screen
  </button>
  <ul class="dropdown-menu dropdown-menu-end dropdown-menu-lg-start">
    <li><button class="dropdown-item" type="button">Action</button></li>
    <li><button class="dropdown-item" type="button">Another action</button></li>
    <li><button class="dropdown-item" type="button">Something else here</button></li>
  </ul>
</div>

Note that you don’t need to add a data-bs-display="static" attribute to dropdown buttons in navbars, since Popper isn’t used in navbars.

Alignment options

Taking most of the options shown above, here’s a small kitchen sink demo of various dropdown alignment options in one place.

<div class="btn-group">
  <button class="btn btn-dropdown dropdown-toggle" type="button" data-bs-toggle="dropdown" aria-expanded="false">
    Dropdown
  </button>
  <ul class="dropdown-menu">
    <li><a class="dropdown-item" href="#">Menu item</a></li>
    <li><a class="dropdown-item" href="#">Menu item</a></li>
    <li><a class="dropdown-item" href="#">Menu item</a></li>
  </ul>
</div>

<div class="btn-group">
  <button type="button" class="btn btn-dropdown dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">
    Right-aligned menu
  </button>
  <ul class="dropdown-menu dropdown-menu-end">
    <li><a class="dropdown-item" href="#">Menu item</a></li>
    <li><a class="dropdown-item" href="#">Menu item</a></li>
    <li><a class="dropdown-item" href="#">Menu item</a></li>
  </ul>
</div>

<div class="btn-group">
  <button type="button" class="btn btn-dropdown dropdown-toggle" data-bs-toggle="dropdown" data-bs-display="static" aria-expanded="false">
    Left-aligned, right-aligned lg
  </button>
  <ul class="dropdown-menu dropdown-menu-lg-end">
    <li><a class="dropdown-item" href="#">Menu item</a></li>
    <li><a class="dropdown-item" href="#">Menu item</a></li>
    <li><a class="dropdown-item" href="#">Menu item</a></li>
  </ul>
</div>

<div class="btn-group">
  <button type="button" class="btn btn-dropdown dropdown-toggle" data-bs-toggle="dropdown" data-bs-display="static" aria-expanded="false">
    Right-aligned, left-aligned lg
  </button>
  <ul class="dropdown-menu dropdown-menu-end dropdown-menu-lg-start">
    <li><a class="dropdown-item" href="#">Menu item</a></li>
    <li><a class="dropdown-item" href="#">Menu item</a></li>
    <li><a class="dropdown-item" href="#">Menu item</a></li>
  </ul>
</div>

<div class="btn-group dropstart">
  <button type="button" class="btn btn-dropdown dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">
    Dropstart
  </button>
  <ul class="dropdown-menu">
    <li><a class="dropdown-item" href="#">Menu item</a></li>
    <li><a class="dropdown-item" href="#">Menu item</a></li>
    <li><a class="dropdown-item" href="#">Menu item</a></li>
  </ul>
</div>

<div class="btn-group dropend">
  <button type="button" class="btn btn-dropdown dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">
    Dropend
  </button>
  <ul class="dropdown-menu">
    <li><a class="dropdown-item" href="#">Menu item</a></li>
    <li><a class="dropdown-item" href="#">Menu item</a></li>
    <li><a class="dropdown-item" href="#">Menu item</a></li>
  </ul>
</div>

<div class="btn-group dropup">
  <button type="button" class="btn btn-dropdown dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">
    Dropup
  </button>
  <ul class="dropdown-menu">
    <li><a class="dropdown-item" href="#">Menu item</a></li>
    <li><a class="dropdown-item" href="#">Menu item</a></li>
    <li><a class="dropdown-item" href="#">Menu item</a></li>
  </ul>
</div>

Menu content

Headers

Add a header to label sections of actions in any dropdown menu.

<ul class="dropdown-menu">
  <li><h6 class="dropdown-header">Dropdown header</h6></li>
  <li><a class="dropdown-item" href="#">Action</a></li>
  <li><a class="dropdown-item" href="#">Another action</a></li>
</ul>

Dividers

Separate groups of related menu items with a divider.

<ul class="dropdown-menu">
  <li><a class="dropdown-item" href="#">Action</a></li>
  <li><a class="dropdown-item" href="#">Another action</a></li>
  <li><a class="dropdown-item" href="#">Something else here</a></li>
  <li><hr class="dropdown-divider" /></li>
  <li><a class="dropdown-item" href="#">Separated link</a></li>
</ul>

Text

Place any freeform text within a dropdown menu with text and use spacing utilities. Note that you’ll likely need additional sizing styles to constrain the menu width.

<div class="dropdown-menu p-4 text-body-secondary" style="max-width: 200px;">
  <p>
    Some example text that’s free-flowing within the dropdown menu.
  </p>
  <p class="mb-0">
    And this is more example text.
  </p>
</div>

Forms

Put a form within a dropdown menu, or make it into a dropdown menu, and use margin or padding utilities to give it the negative space you require.

<div class="dropdown-menu">
  <form class="px-4 py-3">
    <div class="mb-3">
      <label for="exampleDropdownFormEmail1" class="form-label">Email address</label>
      <input type="email" class="form-control" id="exampleDropdownFormEmail1" placeholder="email@example.com">
    </div>
    <div class="mb-3">
      <label for="exampleDropdownFormPassword1" class="form-label">Password</label>
      <input type="password" class="form-control" id="exampleDropdownFormPassword1" placeholder="Password">
    </div>
    <div class="mb-3">
      <div class="form-check">
        <input type="checkbox" class="form-check-input" id="dropdownCheck">
        <label class="form-check-label" for="dropdownCheck">
          Remember me
        </label>
      </div>
    </div>
    <button type="submit" class="btn btn-primary mt-2">Sign in</button>
  </form>
  <div class="dropdown-divider"></div>
  <a class="dropdown-item" href="#">New around here? Sign up</a>
  <a class="dropdown-item" href="#">Forgot password?</a>
</div>

<div class="dropdown">
  <button type="button" class="btn btn-primary dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false" data-bs-auto-close="outside">
    Dropdown form
  </button>
  <form class="dropdown-menu p-4">
    <div class="mb-3">
      <label for="exampleDropdownFormEmail2" class="form-label">Email address</label>
      <input type="email" class="form-control" id="exampleDropdownFormEmail2" placeholder="email@example.com">
    </div>
    <div class="mb-3">
      <label for="exampleDropdownFormPassword2" class="form-label">Password</label>
      <input type="password" class="form-control" id="exampleDropdownFormPassword2" placeholder="Password">
    </div>
    <div class="mb-3">
      <div class="form-check">
        <input type="checkbox" class="form-check-input" id="dropdownCheck2">
        <label class="form-check-label" for="dropdownCheck2">
          Remember me
        </label>
      </div>
    </div>
    <button type="submit" class="btn btn-primary mt-2">Sign in</button>
  </form>
</div>

Dropdown options

Use data-bs-offset or data-bs-reference to change the location of the dropdown.

<div class="d-flex">
  <div class="dropdown me-1">
    <button type="button" class="btn btn-dropdown dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false" data-bs-offset="10,20">
      Offset
    </button>
    <ul class="dropdown-menu">
      <li><a class="dropdown-item" href="#">Action</a></li>
      <li><a class="dropdown-item" href="#">Another action</a></li>
      <li><a class="dropdown-item" href="#">Something else here</a></li>
    </ul>
  </div>
  <div class="btn-group">
    <button type="button" class="btn btn-outline-secondary">Reference</button>
    <button type="button" class="btn btn-outline-secondary dropdown-toggle dropdown-toggle-split" data-bs-toggle="dropdown" aria-expanded="false" data-bs-reference="parent">
      <span class="visually-hidden">Toggle Dropdown</span>
    </button>
    <ul class="dropdown-menu">
      <li><a class="dropdown-item" href="#">Action</a></li>
      <li><a class="dropdown-item" href="#">Another action</a></li>
      <li><a class="dropdown-item" href="#">Something else here</a></li>
      <li><hr class="dropdown-divider" /></li>
      <li><a class="dropdown-item" href="#">Separated link</a></li>
    </ul>
  </div>
</div>

Auto close behavior

By default, the dropdown menu is closed when clicking inside or outside the dropdown menu. You can use the autoClose option to change this behavior of the dropdown.

<div class="btn-group">
  <button class="btn btn-dropdown dropdown-toggle" type="button" data-bs-toggle="dropdown" data-bs-auto-close="true" aria-expanded="false">
    Default dropdown
  </button>
  <ul class="dropdown-menu">
    <li><a class="dropdown-item" href="#">Menu item</a></li>
    <li><a class="dropdown-item" href="#">Menu item</a></li>
    <li><a class="dropdown-item" href="#">Menu item</a></li>
  </ul>
</div>

<div class="btn-group">
  <button class="btn btn-dropdown dropdown-toggle" type="button" data-bs-toggle="dropdown" data-bs-auto-close="true" aria-expanded="false">
    Default dropdown
  </button>
  <ul class="dropdown-menu">
    <li><a class="dropdown-item" href="#">Menu item</a></li>
    <li><a class="dropdown-item" href="#">Menu item</a></li>
    <li><a class="dropdown-item" href="#">Menu item</a></li>
  </ul>
</div>

<div class="btn-group">
  <button class="btn btn-dropdown dropdown-toggle" type="button" data-bs-toggle="dropdown" data-bs-auto-close="inside" aria-expanded="false">
    Clickable inside
  </button>
  <ul class="dropdown-menu">
    <li><a class="dropdown-item" href="#">Menu item</a></li>
    <li><a class="dropdown-item" href="#">Menu item</a></li>
    <li><a class="dropdown-item" href="#">Menu item</a></li>
  </ul>
</div>

<div class="btn-group">
  <button class="btn btn-dropdown dropdown-toggle" type="button" data-bs-toggle="dropdown" data-bs-auto-close="outside" aria-expanded="false">
    Clickable outside
  </button>
  <ul class="dropdown-menu">
    <li><a class="dropdown-item" href="#">Menu item</a></li>
    <li><a class="dropdown-item" href="#">Menu item</a></li>
    <li><a class="dropdown-item" href="#">Menu item</a></li>
  </ul>
</div>

<div class="btn-group">
  <button class="btn btn-dropdown dropdown-toggle" type="button" data-bs-toggle="dropdown" data-bs-auto-close="false" aria-expanded="false">
    Manual close
  </button>
  <ul class="dropdown-menu">
    <li><a class="dropdown-item" href="#">Menu item</a></li>
    <li><a class="dropdown-item" href="#">Menu item</a></li>
    <li><a class="dropdown-item" href="#">Menu item</a></li>
  </ul>
</div>

CSS

Variables

Added in v5.2.0

As part of Boosted’s evolving CSS variables approach, dropdowns now use local CSS variables on .dropdown-menu for enhanced real-time customization. Values for the CSS variables are set via Sass, so Sass customization is still supported, too.

--#{$prefix}dropdown-zindex: #{$zindex-dropdown};
--#{$prefix}dropdown-min-width: #{$dropdown-min-width};
// Boosted mod: no --#{$prefix}dropdown-padding-x
--#{$prefix}dropdown-padding-y: #{$dropdown-padding-y};
--#{$prefix}dropdown-spacer: #{$dropdown-spacer};
@include rfs($dropdown-font-size, --#{$prefix}dropdown-font-size);
--#{$prefix}dropdown-line-height: #{$dropdown-line-height}; // Boosted mod
--#{$prefix}dropdown-color: #{$dropdown-color};
--#{$prefix}dropdown-bg: #{$dropdown-bg};
--#{$prefix}dropdown-border-color: #{$dropdown-border-color};
--#{$prefix}dropdown-border-radius: #{$dropdown-border-radius};
--#{$prefix}dropdown-border-width: #{$dropdown-border-width};
--#{$prefix}dropdown-inner-border-radius: #{$dropdown-inner-border-radius};
--#{$prefix}dropdown-divider-bg: #{$dropdown-divider-bg};
--#{$prefix}dropdown-divider-margin-y: #{$dropdown-divider-margin-y};
--#{$prefix}dropdown-box-shadow: #{$dropdown-box-shadow};
--#{$prefix}dropdown-link-color: #{$dropdown-link-color};
--#{$prefix}dropdown-link-hover-color: #{$dropdown-link-hover-color};
--#{$prefix}dropdown-link-hover-bg: #{$dropdown-link-hover-bg};
--#{$prefix}dropdown-link-active-color: #{$dropdown-link-active-color};
--#{$prefix}dropdown-link-active-bg: #{$dropdown-link-active-bg};
--#{$prefix}dropdown-link-disabled-color: #{$dropdown-link-disabled-color};
--#{$prefix}dropdown-item-padding-x: #{$dropdown-item-padding-x};
--#{$prefix}dropdown-item-padding-y: #{$dropdown-item-padding-y};
--#{$prefix}dropdown-item-font-weight: #{$font-weight-bold}; // Boosted mod
--#{$prefix}dropdown-header-color: #{$dropdown-header-color};
--#{$prefix}dropdown-header-padding-x: #{$dropdown-header-padding-x};
--#{$prefix}dropdown-header-padding-y: #{$dropdown-header-padding-y};

Sass variables

Variables for all dropdowns:

$dropdown-min-width:                10rem;
$dropdown-padding-x:                $spacer * .5; // Boosted mod: instead of `0`
$dropdown-padding-y:                0; // Boosted mod: instead of `.5rem`
$dropdown-spacer:                   0; // Boosted mod: instead of `.125rem`
$dropdown-font-size:                $font-size-base;
$dropdown-line-height:              $line-height-base; // Boosted mod
$dropdown-color:                    var(--#{$prefix}body-color);
$dropdown-bg:                       var(--#{$prefix}body-bg);
$dropdown-border-color:             var(--#{$prefix}border-color-subtle); // Boosted mod: instead of `var(--#{$prefix}border-color-translucent)`
$dropdown-border-radius:            var(--#{$prefix}border-radius);
$dropdown-border-width:             var(--#{$prefix}border-width);
$dropdown-inner-border-radius:      0; // Boosted mod: instead of `calc(#{$dropdown-border-radius} - #{$dropdown-border-width})`
$dropdown-divider-bg:               $dropdown-border-color;
$dropdown-divider-margin-y:         $spacer * .25; // Boosted mod: instead of `$spacer * .5`
$dropdown-box-shadow:               var(--#{$prefix}box-shadow);

$dropdown-link-color:               null; // Boosted mod: instead of `var(--#{$prefix}body-color)`
$dropdown-link-hover-color:         $dropdown-link-color;
$dropdown-link-hover-bg:            var(--#{$prefix}secondary-bg); // Boosted mod: instead of `var(--#{$prefix}tertiary-bg)`

$dropdown-link-active-color:        $dropdown-link-color; // Boosted mod: instead of `$component-active-color`
$dropdown-link-active-bg:           var(--#{$prefix}tertiary-active-bg); // Boosted mod: instead of `$component-active-bg`

$dropdown-link-disabled-color:      var(--#{$prefix}disabled-color); // Boosted mod: instead of `var(--#{$prefix}tertiary-color)`

$dropdown-item-padding-y:           $spacer * .5; // Boosted mod: instead of `$spacer * .25`
$dropdown-item-padding-x:           $spacer * .5; // Boosted mod: instead of `$spacer`

$dropdown-header-color:             null; // Boosted mod: instead of `$gray-600`
$dropdown-header-padding-x:         $dropdown-item-padding-x;
$dropdown-header-padding-y:         $spacer; // Boosted mod: instead of `$dropdown-padding-y`
// fusv-disable
$dropdown-header-padding:           $dropdown-header-padding-y $dropdown-header-padding-x; // Deprecated in v5.2.0
// fusv-enable

Variables for the CSS-based carets that indicate a dropdown’s interactivity:

$caret-width:                 add($spacer * .25, var(--#{$prefix}border-width));
$caret-vertical-align:        center;
$caret-spacing:               $spacer * .5;

Sass mixins

Mixins are used to generate the CSS-based carets and can be found in scss/mixins/_caret.scss.

@mixin caret-down($width: $caret-width) {
  border-top: $width solid;
  border-right: $width solid transparent;
  border-bottom: 0;
  border-left: $width solid transparent;
}

@mixin caret-up($width: $caret-width) {
  border-top: 0;
  border-right: $width solid transparent;
  border-bottom: $width solid;
  border-left: $width solid transparent;
}

@mixin caret-end($width: $caret-width) {
  border-top: $width solid transparent;
  border-right: 0;
  border-bottom: $width solid transparent;
  border-left: $width solid;
}

@mixin caret-start($width: $caret-width) {
  border-top: $width solid transparent;
  border-right: $width solid;
  border-bottom: $width solid transparent;
}

@mixin caret(
  $direction: down,
  $width: $caret-width,
  $spacing: $caret-spacing,
  $vertical-align: $caret-vertical-align,
  $accordion: false // Boosted mod: $accordion param only there in Boosted
) {
  @if $enable-caret {
    &::after {
      display: inline-block;
      // Boosted mod: flexbox FTW!
      align-self: $vertical-align;
      @if ($accordion == false) {
        margin-left: $spacing;
      } @else {
        margin: 0 $spacing 0 auto;
      }
      // End mod
      content: "";
      @if $direction == down {
        @include caret-down($width);
        // stylelint-disable-next-line function-disallowed-list
        transform: translateY(calc(var(--#{$prefix}border-width) * .5)); // Boosted mod
      } @else if $direction == up {
        @include caret-up($width);
      } @else if $direction == end {
        @include caret-end($width);
      }
    }

    @if $direction == start {
      &::after {
        display: none;
      }

      &::before {
        // stylelint-disable-next-line declaration-no-important
        position: static !important; // Boosted mod: prevent custom split buttons to interfere
        display: inline-block;
        align-self: $vertical-align; // Boosted mod: flexbox FTW!
        margin-right: $spacing;
        // stylelint-disable-next-line declaration-no-important
        color: unset !important; // Boosted mod: prevent custom split buttons to interfere
        content: "";
        @include caret-start($width);
      }
    }

    &:empty::after {
      margin-left: 0;
    }
  }
}

Usage

Via data attributes or JavaScript, the dropdown plugin toggles hidden content (dropdown menus) by toggling the .show class on the parent .dropdown-menu. The data-bs-toggle="dropdown" attribute is relied on for closing dropdown menus at an application level, so it’s a good idea to always use it.

Via data attributes

Add data-bs-toggle="dropdown" to a link or button to toggle a dropdown.

<div class="dropdown">
  <button type="button" data-bs-toggle="dropdown" aria-expanded="false">
    Dropdown trigger
  </button>
  <ul class="dropdown-menu">
    ...
  </ul>
</div>

Via JavaScript

Call the dropdowns via JavaScript:

const dropdownElementList = document.querySelectorAll('.dropdown-toggle')
const dropdownList = [...dropdownElementList].map(dropdownToggleEl => new boosted.Dropdown(dropdownToggleEl))

Options

As options can be passed via data attributes or JavaScript, you can append an option name to data-bs-, as in data-bs-animation="{value}". Make sure to change the case type of the option name from “camelCase” to “kebab-case” when passing the options via data attributes. For example, use data-bs-custom-class="beautifier" instead of data-bs-customClass="beautifier".

As of Boosted 5.2.0, all components support an experimental reserved data attribute data-bs-config that can house simple component configuration as a JSON string. When an element has data-bs-config='{"delay":0, "title":123}' and data-bs-title="456" attributes, the final title value will be 456 and the separate data attributes will override values given on data-bs-config. In addition, existing data attributes are able to house JSON values like data-bs-delay='{"show":0,"hide":150}'.

The final configuration object is the merged result of data-bs-config, data-bs-, and js object where the latest given key-value overrides the others.

Using function with popperConfig

const dropdown = new boosted.Dropdown(element, {
  popperConfig(defaultBsPopperConfig) {
    // const newPopperConfig = {...}
    // use defaultBsPopperConfig if needed...
    // return newPopperConfig
  }
})

Methods

Events

All dropdown events are fired at the toggling element and then bubbled up. So you can also add event listeners on the .dropdown-menu's parent element. hide.bs.dropdown and hidden.bs.dropdown events have a clickEvent property (only when the original Event type is click) that contains an Event Object for the click event.

const myDropdown = document.getElementById('myDropdown')
myDropdown.addEventListener('show.bs.dropdown', event => {
  // do something...
})