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Bootstrap/site/content/docs/5.1/components/buttons.md
2022-02-14 19:00:59 -08:00

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docs Buttons Use Bootstrap's custom button styles for actions in forms, dialogs, and more with support for multiple sizes, states, and more. components true

Examples

Bootstrap includes several predefined button styles, each serving its own semantic purpose, with a few extras thrown in for more control.

{{< example >}} {{< buttons.inline >}} {{- range (index $.Site.Data "theme-colors") }} {{ .name | title }} {{- end -}} {{< /buttons.inline >}}

Link {{< /example >}}

{{< callout info >}} {{< partial "callout-warning-color-assistive-technologies.md" >}} {{< /callout >}}

Disable text wrapping

If you don't want the button text to wrap, you can add the .text-nowrap class to the button. In Sass, you can set $btn-white-space: nowrap to disable text wrapping for each button.

Button tags

The .btn classes are designed to be used with the <button> element. However, you can also use these classes on <a> or <input> elements (though some browsers may apply a slightly different rendering).

When using button classes on <a> elements that are used to trigger in-page functionality (like collapsing content), rather than linking to new pages or sections within the current page, these links should be given a role="button" to appropriately convey their purpose to assistive technologies such as screen readers.

{{< example >}} Link Button {{< /example >}}

Outline buttons

In need of a button, but not the hefty background colors they bring? Replace the default modifier classes with the .btn-outline-* ones to remove all background images and colors on any button.

{{< example >}} {{< buttons.inline >}} {{- range (index $.Site.Data "theme-colors") }} {{ .name | title }} {{- end -}} {{< /buttons.inline >}} {{< /example >}}

{{< callout info >}} Some of the button styles use a relatively light foreground color, and should only be used on a dark background in order to have sufficient contrast. {{< /callout >}}

Sizes

Fancy larger or smaller buttons? Add .btn-lg or .btn-sm for additional sizes.

{{< example >}} Large button Large button {{< /example >}}

{{< example >}} Small button Small button {{< /example >}}

You can even roll your own custom sizing with CSS variables:

{{< example >}} Custom button {{< /example >}}

Disabled state

Make buttons look inactive by adding the disabled boolean attribute to any <button> element. Disabled buttons have pointer-events: none applied to, preventing hover and active states from triggering.

{{< example >}} Primary button Button Primary button Button {{< /example >}}

Disabled buttons using the <a> element behave a bit different:

  • <a>s don't support the disabled attribute, so you must add the .disabled class to make it visually appear disabled.
  • Some future-friendly styles are included to disable all pointer-events on anchor buttons.
  • Disabled buttons using <a> should include the aria-disabled="true" attribute to indicate the state of the element to assistive technologies.
  • Disabled buttons using <a> should not include the href attribute.

{{< example >}} Primary link Link {{< /example >}}

To cover cases where you have to keep the href attribute on a disabled link, the .disabled class uses pointer-events: none to try to disable the link functionality of <a>s. Note that this CSS property is not yet standardized for HTML, but all modern browsers support it. In addition, even in browsers that do support pointer-events: none, keyboard navigation remains unaffected, meaning that sighted keyboard users and users of assistive technologies will still be able to activate these links. So to be safe, in addition to aria-disabled="true", also include a tabindex="-1" attribute on these links to prevent them from receiving keyboard focus, and use custom JavaScript to disable their functionality altogether.

{{< example >}} Primary link Link {{< /example >}}

Block buttons

Create responsive stacks of full-width, "block buttons" like those in Bootstrap 4 with a mix of our display and gap utilities. By using utilities instead of button specific classes, we have much greater control over spacing, alignment, and responsive behaviors.

{{< example >}}

Button Button
{{< /example >}}

Here we create a responsive variation, starting with vertically stacked buttons until the md breakpoint, where .d-md-block replaces the .d-grid class, thus nullifying the gap-2 utility. Resize your browser to see them change.

{{< example >}}

Button Button
{{< /example >}}

You can adjust the width of your block buttons with grid column width classes. For example, for a half-width "block button", use .col-6. Center it horizontally with .mx-auto, too.

{{< example >}}

Button Button
{{< /example >}}

Additional utilities can be used to adjust the alignment of buttons when horizontal. Here we've taken our previous responsive example and added some flex utilities and a margin utility on the button to right align the buttons when they're no longer stacked.

{{< example >}}

Button Button
{{< /example >}}

Button plugin

The button plugin allows you to create simple on/off toggle buttons.

{{< callout info >}} Visually, these toggle buttons are identical to the [checkbox toggle buttons]({{< docsref "/forms/checks-radios#checkbox-toggle-buttons" >}}). However, they are conveyed differently by assistive technologies: the checkbox toggles will be announced by screen readers as "checked"/"not checked" (since, despite their appearance, they are fundamentally still checkboxes), whereas these toggle buttons will be announced as "button"/"button pressed". The choice between these two approaches will depend on the type of toggle you are creating, and whether or not the toggle will make sense to users when announced as a checkbox or as an actual button. {{< /callout >}}

Toggle states

Add data-bs-toggle="button" to toggle a button's active state. If you're pre-toggling a button, you must manually add the .active class and aria-pressed="true" to ensure that it is conveyed appropriately to assistive technologies.

{{< example >}} Toggle button Active toggle button Disabled toggle button {{< /example >}}

{{< example >}} Toggle link Active toggle link Disabled toggle link {{< /example >}}

Methods

You can create a button instance with the button constructor, for example:

var button = document.getElementById('myButton')
var bsButton = new bootstrap.Button(button)
Method Description
toggle Toggles push state. Gives the button the appearance that it has been activated.
dispose Destroys an element's button. (Removes stored data on the DOM element)
getInstance Static method which allows you to get the button instance associated to a DOM element, you can use it like this: bootstrap.Button.getInstance(element)
getOrCreateInstance Static method which returns a button instance associated to a DOM element or create a new one in case it wasn't initialized. You can use it like this: bootstrap.Button.getOrCreateInstance(element)

For example, to toggle all buttons

var buttons = document.querySelectorAll('.btn')
buttons.forEach(function (button) {
  var button = new bootstrap.Button(button)
  button.toggle()
})

CSS

Variables

Added in v5.2.0

As part of Bootstrap's evolving CSS variables approach, buttons now use local CSS variables on .btn for enhanced real-time customization. Values for the CSS variables are set via Sass, so Sass customization is still supported, too.

{{< scss-docs name="btn-css-vars" file="scss/_buttons.scss" >}}

Each .btn-* modifier class updates the appropriate CSS variables to minimize additional CSS rules with our button-variant(), button-outline-variant(), and button-size() mixins.

Here's an example of building a custom .btn-* modifier class like we do for the buttons unique to our docs by reassigning Bootstrap's CSS variables with a mixture of our own CSS and Sass variables.

Custom button

{{< scss-docs name="btn-css-vars-example" file="site/assets/scss/_buttons.scss" >}}

Sass variables

{{< scss-docs name="btn-variables" file="scss/_variables.scss" >}}

Sass mixins

There are three mixins for buttons: button and button outline variant mixins (both based on $theme-colors), plus a button size mixin.

{{< scss-docs name="btn-variant-mixin" file="scss/mixins/_buttons.scss" >}}

{{< scss-docs name="btn-outline-variant-mixin" file="scss/mixins/_buttons.scss" >}}

{{< scss-docs name="btn-size-mixin" file="scss/mixins/_buttons.scss" >}}

Sass loops

Button variants (for regular and outline buttons) use their respective mixins with our $theme-colors map to generate the modifier classes in scss/_buttons.scss.

{{< scss-docs name="btn-variant-loops" file="scss/_buttons.scss" >}}