8.9 KiB
| layout | title |
|---|---|
| page | Buttons |
Buttons are used to execute actions in forms, dialogs, and more. Use any of the available button classes to quickly create a styled button.
Examples
Bootstrap includes six predefined button styles, each serving its own semantic purpose.
{% example html %}
Primary
Secondary
Success
Warning
Danger
Link {% endexample %}
{% callout warning %}
Conveying meaning to assistive technologies
Using color to add meaning to a button only provides a visual indication, which will not be conveyed to users of assistive technologies – such as screen readers. Ensure that information denoted by the color is either obvious from the content itself (the visible text of the button), or is included through alternative means, such as additional text hidden with the .sr-only class.
{% endcallout %}
Button tags
As a best practice, we highly recommend using the <button> element whenever possible to ensure matching cross-browser rendering. However, you may also use button classes on <a>, <button>, or <input> elements.
When using button classes on <a> elements, be sure to include the role="button" for improved accessibility.
{% example html %} Link Button {% endexample %}
Sizes
Fancy larger or smaller buttons? Add .btn-lg, .btn-sm, or .btn-xs for additional sizes.
{% example html %} Large button Large button {% endexample %}
{% example html %} Small button Small button {% endexample %}
{% example html %} Extra small button Extra small button {% endexample %}
Create block level buttons—those that span the full width of a parent—by adding .btn-block.
{% example html %} Block level button Block level button {% endexample %}
Active state
Buttons will appear pressed (with a darker background, darker border, and inset shadow) when active. There's no need to add a class to <button>s as they use a pseudo-class. However, you can still force the same active appearance with .active (and include the aria-pressed="true" attribute) should you need to replicate the state programmatically.
{% example html %} Primary link Link {% endexample %}
Disabled state
Make buttons look unclickable by adding the disabled boolean attribute to any <button> element.
{% example html %} Primary button Button {% endexample %}
As <a> elements don't support the disabled attribute, you must add the .disabled class to fake it.
{% example html %} Primary link Link {% endexample %}
{% callout warning %}
Cross-browser compatibility
If you add the disabled attribute to a <button>, Internet Explorer 9 and below will render text gray with a nasty text-shadow that we cannot fix.
{% endcallout %}
{% callout warning %}
Link functionality caveat
This class uses pointer-events: none to try to disable the link functionality of <a>s, but that CSS property is not yet standardized and isn't fully supported in Opera 18 and below, or in Internet Explorer 11. 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, use custom JavaScript to disable such links.
{% endcallout %}
{% callout warning %}
Context-specific usage
While button classes can be used on <a> and <button> elements, only <button> elements are supported within our nav and navbar components.
{% endcallout %}
JavaScript behavior
Do more with buttons. Control button states or create groups of buttons for more components like toolbars.
Custom states
Use JavaScript to change the text and "state" of a particular button. For the sake of this demonstration, we are using data-loading-text and $().button('loading'), but that's not the only state you can use. Custom strings of text can also be used with $().button(string).
Heads up! You'll likely need to work around Firefox's persisted form control states across page loads bug (e.g., disabled and checked states) with autocomplete="off". See Mozilla bug #654072 for details.
{% example html %} Loading state
{% endexample %}
Single toggle
Add data-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 the <button>.
{% example html %} Single toggle {% endexample %}
Checkbox and radio
Bootstrap's .button styles can be applied to other elements, such as <label>s, to provide checkbox or radio style button toggling. Add data-toggle="buttons" to a .btn-group containing those modified buttons to enable toggling in their respective styles.
The checked state for these buttons is only updated via click event on the button. If you use another method to update the input—e.g., with <input type="reset"> or by manually applying the input's checked property—you'll need to toggle .active on the <label> manually.
Note that pre-checked buttons require you to manually add the .active class to the input's <label>.
{% example html %}
{% example html %}
Methods
$().button('toggle')
Toggles push state. Gives the button the appearance that it has been activated.
$().button('reset')
Resets button state—swaps text to original text.
$().button(string)
Swaps text to any data defined text state.
{% highlight html %} ...
{% endhighlight %}