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Bootstrap/site/content/docs/5.0/components/buttons.md
Matt Shaw de8dbd72d8
correct "breakpoint" typo (#32191)
breakpoing --> breakpoint
2020-11-18 18:15:28 +02:00

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---
layout: docs
title: Buttons
description: Use Bootstrap's custom button styles for actions in forms, dialogs, and more with support for multiple sizes, states, and more.
group: components
toc: 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 $.Site.Data "theme-colors") }}
<button type="button" class="btn btn-{{ .name }}">{{ .name | title }}</button>
{{- end -}}
{{< /buttons.inline >}}
<button type="button" class="btn btn-link">Link</button>
{{< /example >}}
{{< callout info >}}
{{< partial "callout-warning-color-assistive-technologies.md" >}}
{{< /callout >}}
## Disable text wrapping
If you don't want the button text to wrap, you can add the `.text-nowrap` class to the button. In Sass, you can set `$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 >}}
<a class="btn btn-primary" href="#" role="button">Link</a>
<button class="btn btn-primary" type="submit">Button</button>
<input class="btn btn-primary" type="button" value="Input">
<input class="btn btn-primary" type="submit" value="Submit">
<input class="btn btn-primary" type="reset" value="Reset">
{{< /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") }}
<button type="button" class="btn btn-outline-{{ .name }}">{{ .name | title }}</button>
{{- 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 >}}
<button type="button" class="btn btn-primary btn-lg">Large button</button>
<button type="button" class="btn btn-secondary btn-lg">Large button</button>
{{< /example >}}
{{< example >}}
<button type="button" class="btn btn-primary btn-sm">Small button</button>
<button type="button" class="btn btn-secondary btn-sm">Small button</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 >}}
<button type="button" class="btn btn-lg btn-primary" disabled>Primary button</button>
<button type="button" class="btn btn-secondary btn-lg" disabled>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 should include the `aria-disabled="true"` attribute to indicate the state of the element to assistive technologies.
{{< example >}}
<a href="#" class="btn btn-primary btn-lg disabled" tabindex="-1" role="button" aria-disabled="true">Primary link</a>
<a href="#" class="btn btn-secondary btn-lg disabled" tabindex="-1" role="button" aria-disabled="true">Link</a>
{{< /example >}}
{{< callout warning >}}
##### Link functionality caveat
The `.disabled` class uses `pointer-events: none` to try to disable the link functionality of `<a>`s, but that CSS property is not yet standardized. 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.
{{< /callout >}}
## 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 >}}
<div class="d-grid gap-2">
<button class="btn btn-primary" type="button">Button</button>
<button class="btn btn-primary" type="button">Button</button>
</div>
{{< /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 >}}
<div class="d-grid gap-2 d-md-block">
<button class="btn btn-primary" type="button">Button</button>
<button class="btn btn-primary" type="button">Button</button>
</div>
{{< /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 >}}
<div class="d-grid gap-2 col-6 mx-auto">
<button class="btn btn-primary" type="button">Button</button>
<button class="btn btn-primary" type="button">Button</button>
</div>
{{< /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 >}}
<div class="d-grid gap-2 d-md-flex justify-content-md-end">
<button class="btn btn-primary mr-md-2" type="button">Button</button>
<button class="btn btn-primary" type="button">Button</button>
</div>
{{< /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 >}}
<button type="button" class="btn btn-primary" data-bs-toggle="button" autocomplete="off">Toggle button</button>
<button type="button" class="btn btn-primary active" data-bs-toggle="button" autocomplete="off" aria-pressed="true">Active toggle button</button>
<button type="button" class="btn btn-primary" disabled data-bs-toggle="button" autocomplete="off">Disabled toggle button</button>
{{< /example >}}
{{< example >}}
<a href="#" class="btn btn-primary" role="button" data-bs-toggle="button">Toggle link</a>
<a href="#" class="btn btn-primary active" role="button" data-bs-toggle="button" aria-pressed="true">Active toggle link</a>
<a href="#" class="btn btn-primary disabled" tabindex="-1" aria-disabled="true" role="button" data-bs-toggle="button">Disabled toggle link</a>
{{< /example >}}
### Methods
You can create a button instance with the button constructor, for example:
```js
var button = document.getElementById('myButton')
var bsButton = new bootstrap.Button(button)
```
<table class="table">
<thead>
<tr>
<th>Method</th>
<th>Description</th>
</tr>
</thead>
<tbody>
<tr>
<td>
<code>toggle</code>
</td>
<td>
Toggles push state. Gives the button the appearance that it has been activated.
</td>
</tr>
<tr>
<td>
<code>dispose</code>
</td>
<td>
Destroys an element's button. (Removes stored data on the DOM element)
</td>
</tr>
</tbody>
</table>
For example, to toggle all buttons
```js
var buttons = document.querySelectorAll('.btn')
buttons.forEach(function (button) {
var button = new bootstrap.Button(button)
button.toggle()
})
```