Javascript How to Continuously Check if a Header Exists
JavaScript
Bring Bootstrap's components to life with over a dozen custom jQuery plugins. Easily include them all, or one by one.
Individual or compiled
Plugins can be included individually (using Bootstrap's individual *.js
files), or all at once (using bootstrap.js
or the minified bootstrap.min.js
).
Using the compiled JavaScript
Both bootstrap.js
and bootstrap.min.js
contain all plugins in a single file. Include only one.
Plugin dependencies
Some plugins and CSS components depend on other plugins. If you include plugins individually, make sure to check for these dependencies in the docs. Also note that all plugins depend on jQuery (this means jQuery must be included before the plugin files). Consult our bower.json
to see which versions of jQuery are supported.
Data attributes
You can use all Bootstrap plugins purely through the markup API without writing a single line of JavaScript. This is Bootstrap's first-class API and should be your first consideration when using a plugin.
That said, in some situations it may be desirable to turn this functionality off. Therefore, we also provide the ability to disable the data attribute API by unbinding all events on the document namespaced with data-api
. This looks like this:
Alternatively, to target a specific plugin, just include the plugin's name as a namespace along with the data-api namespace like this:
Only one plugin per element via data attributes
Don't use data attributes from multiple plugins on the same element. For example, a button cannot both have a tooltip and toggle a modal. To accomplish this, use a wrapping element.
Programmatic API
We also believe you should be able to use all Bootstrap plugins purely through the JavaScript API. All public APIs are single, chainable methods, and return the collection acted upon.
All methods should accept an optional options object, a string which targets a particular method, or nothing (which initiates a plugin with default behavior):
Each plugin also exposes its raw constructor on a Constructor
property: $.fn.popover.Constructor
. If you'd like to get a particular plugin instance, retrieve it directly from an element: $('[rel="popover"]').data('popover')
.
Default settings
You can change the default settings for a plugin by modifying the plugin's Constructor.DEFAULTS
object:
No conflict
Sometimes it is necessary to use Bootstrap plugins with other UI frameworks. In these circumstances, namespace collisions can occasionally occur. If this happens, you may call .noConflict
on the plugin you wish to revert the value of.
Events
Bootstrap provides custom events for most plugins' unique actions. Generally, these come in an infinitive and past participle form - where the infinitive (ex. show
) is triggered at the start of an event, and its past participle form (ex. shown
) is triggered on the completion of an action.
As of 3.0.0, all Bootstrap events are namespaced.
All infinitive events provide preventDefault
functionality. This provides the ability to stop the execution of an action before it starts.
Version numbers
The version of each of Bootstrap's jQuery plugins can be accessed via the VERSION
property of the plugin's constructor. For example, for the tooltip plugin:
No special fallbacks when JavaScript is disabled
Bootstrap's plugins don't fall back particularly gracefully when JavaScript is disabled. If you care about the user experience in this case, use <noscript>
to explain the situation (and how to re-enable JavaScript) to your users, and/or add your own custom fallbacks.
Third-party libraries
Bootstrap does not officially support third-party JavaScript libraries like Prototype or jQuery UI. Despite .noConflict
and namespaced events, there may be compatibility problems that you need to fix on your own.
About transitions
For simple transition effects, include transition.js
once alongside the other JS files. If you're using the compiled (or minified) bootstrap.js
, there is no need to include this—it's already there.
What's inside
Transition.js is a basic helper for transitionEnd
events as well as a CSS transition emulator. It's used by the other plugins to check for CSS transition support and to catch hanging transitions.
Disabling transitions
Transitions can be globally disabled using the following JavaScript snippet, which must come after transition.js
(or bootstrap.js
or bootstrap.min.js
, as the case may be) has loaded:
Modals are streamlined, but flexible, dialog prompts with the minimum required functionality and smart defaults.
Multiple open modals not supported
Be sure not to open a modal while another is still visible. Showing more than one modal at a time requires custom code.
Modal markup placement
Always try to place a modal's HTML code in a top-level position in your document to avoid other components affecting the modal's appearance and/or functionality.
Due to how HTML5 defines its semantics, the autofocus
HTML attribute has no effect in Bootstrap modals. To achieve the same effect, use some custom JavaScript:
Examples
Static example
A rendered modal with header, body, and set of actions in the footer.
Live demo
Toggle a modal via JavaScript by clicking the button below. It will slide down and fade in from the top of the page.
Make modals accessible
Be sure to add role="dialog"
and aria-labelledby="..."
, referencing the modal title, to .modal
, and role="document"
to the .modal-dialog
itself.
Additionally, you may give a description of your modal dialog with aria-describedby
on .modal
.
Embedding YouTube videos
Embedding YouTube videos in modals requires additional JavaScript not in Bootstrap to automatically stop playback and more. See this helpful Stack Overflow post for more information.
Optional sizes
Modals have two optional sizes, available via modifier classes to be placed on a .modal-dialog
.
Remove animation
For modals that simply appear rather than fade in to view, remove the .fade
class from your modal markup.
Using the grid system
To take advantage of the Bootstrap grid system within a modal, just nest .row
s within the .modal-body
and then use the normal grid system classes.
Have a bunch of buttons that all trigger the same modal, just with slightly different contents? Use event.relatedTarget
and HTML data-*
attributes (possibly via jQuery) to vary the contents of the modal depending on which button was clicked. See the Modal Events docs for details on relatedTarget
,
Usage
The modal plugin toggles your hidden content on demand, via data attributes or JavaScript. It also adds .modal-open
to the <body>
to override default scrolling behavior and generates a .modal-backdrop
to provide a click area for dismissing shown modals when clicking outside the modal.
Via data attributes
Activate a modal without writing JavaScript. Set data-toggle="modal"
on a controller element, like a button, along with a data-target="#foo"
or href="#foo"
to target a specific modal to toggle.
Via JavaScript
Call a modal with id myModal
with a single line of JavaScript:
Options
Options can be passed via data attributes or JavaScript. For data attributes, append the option name to data-
, as in data-backdrop=""
.
Name | type | default | description |
---|---|---|---|
backdrop | boolean or the string 'static' | true | Includes a modal-backdrop element. Alternatively, specify static for a backdrop which doesn't close the modal on click. |
keyboard | boolean | true | Closes the modal when escape key is pressed |
show | boolean | true | Shows the modal when initialized. |
remote | path | false | This option is deprecated since v3.3.0 and has been removed in v4. We recommend instead using client-side templating or a data binding framework, or calling jQuery.load yourself. If a remote URL is provided, content will be loaded one time via jQuery's |
Methods
.modal(options)
Activates your content as a modal. Accepts an optional options object
.
.modal('toggle')
Manually toggles a modal. Returns to the caller before the modal has actually been shown or hidden (i.e. before the shown.bs.modal
or hidden.bs.modal
event occurs).
.modal('show')
Manually opens a modal. Returns to the caller before the modal has actually been shown (i.e. before the shown.bs.modal
event occurs).
.modal('hide')
Manually hides a modal. Returns to the caller before the modal has actually been hidden (i.e. before the hidden.bs.modal
event occurs).
.modal('handleUpdate')
Readjusts the modal's positioning to counter a scrollbar in case one should appear, which would make the modal jump to the left.
Only needed when the height of the modal changes while it is open.
Events
Bootstrap's modal class exposes a few events for hooking into modal functionality.
All modal events are fired at the modal itself (i.e. at the <div class="modal">
).
Event Type | Description |
---|---|
show.bs.modal | This event fires immediately when the show instance method is called. If caused by a click, the clicked element is available as the relatedTarget property of the event. |
shown.bs.modal | This event is fired when the modal has been made visible to the user (will wait for CSS transitions to complete). If caused by a click, the clicked element is available as the relatedTarget property of the event. |
hide.bs.modal | This event is fired immediately when the hide instance method has been called. |
hidden.bs.modal | This event is fired when the modal has finished being hidden from the user (will wait for CSS transitions to complete). |
loaded.bs.modal | This event is fired when the modal has loaded content using the remote option. |
Examples
Add dropdown menus to nearly anything with this simple plugin, including the navbar, tabs, and pills.
Within a navbar
Within pills
Usage
Via data attributes or JavaScript, the dropdown plugin toggles hidden content (dropdown menus) by toggling the .open
class on the parent list item.
On mobile devices, opening a dropdown adds a .dropdown-backdrop
as a tap area for closing dropdown menus when tapping outside the menu, a requirement for proper iOS support. This means that switching from an open dropdown menu to a different dropdown menu requires an extra tap on mobile.
Note: The data-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-toggle="dropdown"
to a link or button to toggle a dropdown.
To keep URLs intact with link buttons, use the data-target
attribute instead of href="#"
.
Via JavaScript
Call the dropdowns via JavaScript:
data-toggle="dropdown"
still required
Regardless of whether you call your dropdown via JavaScript or instead use the data-api, data-toggle="dropdown"
is always required to be present on the dropdown's trigger element.
Options
None
Methods
$().dropdown('toggle')
Toggles the dropdown menu of a given navbar or tabbed navigation.
Events
All dropdown events are fired at the .dropdown-menu
's parent element.
All dropdown events have a relatedTarget
property, whose value is the toggling anchor element.
Event Type | Description |
---|---|
show.bs.dropdown | This event fires immediately when the show instance method is called. |
shown.bs.dropdown | This event is fired when the dropdown has been made visible to the user (will wait for CSS transitions, to complete). |
hide.bs.dropdown | This event is fired immediately when the hide instance method has been called. |
hidden.bs.dropdown | This event is fired when the dropdown has finished being hidden from the user (will wait for CSS transitions, to complete). |
The ScrollSpy plugin is for automatically updating nav targets based on scroll position. Scroll the area below the navbar and watch the active class change. The dropdown sub items will be highlighted as well.
Requires relative positioning
No matter the implementation method, scrollspy requires the use of position: relative;
on the element you're spying on. In most cases this is the <body>
. When scrollspying on elements other than the <body>
, be sure to have a height
set and overflow-y: scroll;
applied.
Via data attributes
To easily add scrollspy behavior to your topbar navigation, add data-spy="scroll"
to the element you want to spy on (most typically this would be the <body>
). Then add the data-target
attribute with the ID or class of the parent element of any Bootstrap .nav
component.
Via JavaScript
After adding position: relative;
in your CSS, call the scrollspy via JavaScript:
Methods
.scrollspy('refresh')
When using scrollspy in conjunction with adding or removing of elements from the DOM, you'll need to call the refresh method like so:
Options
Options can be passed via data attributes or JavaScript. For data attributes, append the option name to data-
, as in data-offset=""
.
Name | type | default | description |
---|---|---|---|
offset | number | 10 | Pixels to offset from top when calculating position of scroll. |
Events
Event Type | Description |
---|---|
activate.bs.scrollspy | This event fires whenever a new item becomes activated by the scrollspy. |
Example tabs
Add quick, dynamic tab functionality to transition through panes of local content, even via dropdown menus. Nested tabs are not supported.
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Usage
Enable tabbable tabs via JavaScript (each tab needs to be activated individually):
You can activate individual tabs in several ways:
Markup
You can activate a tab or pill navigation without writing any JavaScript by simply specifying data-toggle="tab"
or data-toggle="pill"
on an element. Adding the nav
and nav-tabs
classes to the tab ul
will apply the Bootstrap tab styling, while adding the nav
and nav-pills
classes will apply pill styling.
Fade effect
To make tabs fade in, add .fade
to each .tab-pane
. The first tab pane must also have .in
to make the initial content visible.
Methods
$().tab
Activates a tab element and content container. Tab should have either a data-target
or an href
targeting a container node in the DOM. In the above examples, the tabs are the <a>
s with data-toggle="tab"
attributes.
.tab('show')
Selects the given tab and shows its associated content. Any other tab that was previously selected becomes unselected and its associated content is hidden. Returns to the caller before the tab pane has actually been shown (i.e. before the shown.bs.tab
event occurs).
Events
When showing a new tab, the events fire in the following order:
-
hide.bs.tab
(on the current active tab) -
show.bs.tab
(on the to-be-shown tab) -
hidden.bs.tab
(on the previous active tab, the same one as for thehide.bs.tab
event) -
shown.bs.tab
(on the newly-active just-shown tab, the same one as for theshow.bs.tab
event)
If no tab was already active, then the hide.bs.tab
and hidden.bs.tab
events will not be fired.
Event Type | Description |
---|---|
show.bs.tab | This event fires on tab show, but before the new tab has been shown. Use event.target and event.relatedTarget to target the active tab and the previous active tab (if available) respectively. |
shown.bs.tab | This event fires on tab show after a tab has been shown. Use event.target and event.relatedTarget to target the active tab and the previous active tab (if available) respectively. |
hide.bs.tab | This event fires when a new tab is to be shown (and thus the previous active tab is to be hidden). Use event.target and event.relatedTarget to target the current active tab and the new soon-to-be-active tab, respectively. |
hidden.bs.tab | This event fires after a new tab is shown (and thus the previous active tab is hidden). Use event.target and event.relatedTarget to target the previous active tab and the new active tab, respectively. |
Inspired by the excellent jQuery.tipsy plugin written by Jason Frame; Tooltips are an updated version, which don't rely on images, use CSS3 for animations, and data-attributes for local title storage.
Tooltips with zero-length titles are never displayed.
Hover over the links below to see tooltips:
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Static tooltip
Four options are available: top, right, bottom, and left aligned.
Four directions
The tooltip plugin generates content and markup on demand, and by default places tooltips after their trigger element.
Trigger the tooltip via JavaScript:
Markup
The required markup for a tooltip is only a data
attribute and title
on the HTML element you wish to have a tooltip. The generated markup of a tooltip is rather simple, though it does require a position (by default, set to top
by the plugin).
Options
Options can be passed via data attributes or JavaScript. For data attributes, append the option name to data-
, as in data-animation=""
.
Name | Type | Default | Description |
---|---|---|---|
animation | boolean | true | Apply a CSS fade transition to the tooltip |
container | string | false | false | Appends the tooltip to a specific element. Example: |
delay | number | object | 0 | Delay showing and hiding the tooltip (ms) - does not apply to manual trigger type If a number is supplied, delay is applied to both hide/show Object structure is: |
html | boolean | false | Insert HTML into the tooltip. If false, jQuery's text method will be used to insert content into the DOM. Use text if you're worried about XSS attacks. |
placement | string | function | 'top' | How to position the tooltip - top | bottom | left | right | auto. When a function is used to determine the placement, it is called with the tooltip DOM node as its first argument and the triggering element DOM node as its second. The |
selector | string | false | If a selector is provided, tooltip objects will be delegated to the specified targets. In practice, this is used to enable dynamic HTML content to have tooltips added. See this and an informative example. |
template | string | '<div class="tooltip" role="tooltip"><div class="tooltip-arrow"></div><div class="tooltip-inner"></div></div>' | Base HTML to use when creating the tooltip. The tooltip's The outermost wrapper element should have the |
title | string | function | '' | Default title value if If a function is given, it will be called with its |
trigger | string | 'hover focus' | How tooltip is triggered - click | hover | focus | manual. You may pass multiple triggers; separate them with a space. manual cannot be combined with any other trigger. |
viewport | string | object | function | { selector: 'body', padding: 0 } | Keeps the tooltip within the bounds of this element. Example: If a function is given, it is called with the triggering element DOM node as its only argument. The |
Methods
$().tooltip(options)
Attaches a tooltip handler to an element collection.
.tooltip('show')
Reveals an element's tooltip. Returns to the caller before the tooltip has actually been shown (i.e. before the shown.bs.tooltip
event occurs). This is considered a "manual" triggering of the tooltip. Tooltips with zero-length titles are never displayed.
.tooltip('hide')
Hides an element's tooltip. Returns to the caller before the tooltip has actually been hidden (i.e. before the hidden.bs.tooltip
event occurs). This is considered a "manual" triggering of the tooltip.
.tooltip('toggle')
Toggles an element's tooltip. Returns to the caller before the tooltip has actually been shown or hidden (i.e. before the shown.bs.tooltip
or hidden.bs.tooltip
event occurs). This is considered a "manual" triggering of the tooltip.
.tooltip('destroy')
Hides and destroys an element's tooltip. Tooltips that use delegation (which are created using the selector
option) cannot be individually destroyed on descendant trigger elements.
Events
Event Type | Description |
---|---|
show.bs.tooltip | This event fires immediately when the show instance method is called. |
shown.bs.tooltip | This event is fired when the tooltip has been made visible to the user (will wait for CSS transitions to complete). |
hide.bs.tooltip | This event is fired immediately when the hide instance method has been called. |
hidden.bs.tooltip | This event is fired when the tooltip has finished being hidden from the user (will wait for CSS transitions to complete). |
inserted.bs.tooltip | This event is fired after the show.bs.tooltip event when the tooltip template has been added to the DOM. |
Add small overlays of content, like those on the iPad, to any element for housing secondary information.
Popovers whose both title and content are zero-length are never displayed.
Opt-in functionality
For performance reasons, the Tooltip and Popover data-apis are opt-in, meaning you must initialize them yourself.
One way to initialize all popovers on a page would be to select them by their data-toggle
attribute:
Popovers in button groups, input groups, and tables require special setting
When using popovers on elements within a .btn-group
or an .input-group
, or on table-related elements (<td>
, <th>
, <tr>
, <thead>
, <tbody>
, <tfoot>
), you'll have to specify the option container: 'body'
(documented below) to avoid unwanted side effects (such as the element growing wider and/or losing its rounded corners when the popover is triggered).
Popovers on disabled elements require wrapper elements
To add a popover to a disabled
or .disabled
element, put the element inside of a <div>
and apply the popover to that <div>
instead.
Multiple-line links
Sometimes you want to add a popover to a hyperlink that wraps multiple lines. The default behavior of the popover plugin is to center it horizontally and vertically. Add white-space: nowrap;
to your anchors to avoid this.
Examples
Static popover
Four options are available: top, right, bottom, and left aligned.
Popover top
Sed posuere consectetur est at lobortis. Aenean eu leo quam. Pellentesque ornare sem lacinia quam venenatis vestibulum.
Popover right
Sed posuere consectetur est at lobortis. Aenean eu leo quam. Pellentesque ornare sem lacinia quam venenatis vestibulum.
Popover bottom
Sed posuere consectetur est at lobortis. Aenean eu leo quam. Pellentesque ornare sem lacinia quam venenatis vestibulum.
Popover left
Sed posuere consectetur est at lobortis. Aenean eu leo quam. Pellentesque ornare sem lacinia quam venenatis vestibulum.
Live demo
Four directions
Dismiss on next click
Use the focus
trigger to dismiss popovers on the next click that the user makes.
Specific markup required for dismiss-on-next-click
For proper cross-browser and cross-platform behavior, you must use the <a>
tag, not the <button>
tag, and you also must include the role="button"
and tabindex
attributes.
Usage
Enable popovers via JavaScript:
Options
Options can be passed via data attributes or JavaScript. For data attributes, append the option name to data-
, as in data-animation=""
.
Name | Type | Default | Description |
---|---|---|---|
animation | boolean | true | Apply a CSS fade transition to the popover |
container | string | false | false | Appends the popover to a specific element. Example: |
content | string | function | '' | Default content value if If a function is given, it will be called with its |
delay | number | object | 0 | Delay showing and hiding the popover (ms) - does not apply to manual trigger type If a number is supplied, delay is applied to both hide/show Object structure is: |
html | boolean | false | Insert HTML into the popover. If false, jQuery's text method will be used to insert content into the DOM. Use text if you're worried about XSS attacks. |
placement | string | function | 'right' | How to position the popover - top | bottom | left | right | auto. When a function is used to determine the placement, it is called with the popover DOM node as its first argument and the triggering element DOM node as its second. The |
selector | string | false | If a selector is provided, popover objects will be delegated to the specified targets. In practice, this is used to enable dynamic HTML content to have popovers added. See this and an informative example. |
template | string | '<div class="popover" role="tooltip"><div class="arrow"></div><h3 class="popover-title"></h3><div class="popover-content"></div></div>' | Base HTML to use when creating the popover. The popover's The popover's The outermost wrapper element should have the |
title | string | function | '' | Default title value if If a function is given, it will be called with its |
trigger | string | 'click' | How popover is triggered - click | hover | focus | manual. You may pass multiple triggers; separate them with a space. manual cannot be combined with any other trigger. |
viewport | string | object | function | { selector: 'body', padding: 0 } | Keeps the popover within the bounds of this element. Example: If a function is given, it is called with the triggering element DOM node as its only argument. The |
Data attributes for individual popovers
Options for individual popovers can alternatively be specified through the use of data attributes, as explained above.
Methods
$().popover(options)
Initializes popovers for an element collection.
.popover('show')
Reveals an element's popover. Returns to the caller before the popover has actually been shown (i.e. before the shown.bs.popover
event occurs). This is considered a "manual" triggering of the popover. Popovers whose both title and content are zero-length are never displayed.
.popover('hide')
Hides an element's popover. Returns to the caller before the popover has actually been hidden (i.e. before the hidden.bs.popover
event occurs). This is considered a "manual" triggering of the popover.
.popover('toggle')
Toggles an element's popover. Returns to the caller before the popover has actually been shown or hidden (i.e. before the shown.bs.popover
or hidden.bs.popover
event occurs). This is considered a "manual" triggering of the popover.
.popover('destroy')
Hides and destroys an element's popover. Popovers that use delegation (which are created using the selector
option) cannot be individually destroyed on descendant trigger elements.
Events
Event Type | Description |
---|---|
show.bs.popover | This event fires immediately when the show instance method is called. |
shown.bs.popover | This event is fired when the popover has been made visible to the user (will wait for CSS transitions to complete). |
hide.bs.popover | This event is fired immediately when the hide instance method has been called. |
hidden.bs.popover | This event is fired when the popover has finished being hidden from the user (will wait for CSS transitions to complete). |
inserted.bs.popover | This event is fired after the show.bs.popover event when the popover template has been added to the DOM. |
Example alerts
Add dismiss functionality to all alert messages with this plugin.
When using a .close
button, it must be the first child of the .alert-dismissible
and no text content may come before it in the markup.
Usage
Just add data-dismiss="alert"
to your close button to automatically give an alert close functionality. Closing an alert removes it from the DOM.
To have your alerts use animation when closing, make sure they have the .fade
and .in
classes already applied to them.
Methods
$().alert()
Makes an alert listen for click events on descendant elements which have the data-dismiss="alert"
attribute. (Not necessary when using the data-api's auto-initialization.)
$().alert('close')
Closes an alert by removing it from the DOM. If the .fade
and .in
classes are present on the element, the alert will fade out before it is removed.
Events
Bootstrap's alert plugin exposes a few events for hooking into alert functionality.
Event Type | Description |
---|---|
close.bs.alert | This event fires immediately when the close instance method is called. |
closed.bs.alert | This event is fired when the alert has been closed (will wait for CSS transitions to complete). |
Do more with buttons. Control button states or create groups of buttons for more components like toolbars.
Stateful
Add data-loading-text="Loading..."
to use a loading state on a button.
This feature is deprecated since v3.3.5 and has been removed in v4.
Use whichever state you like!
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. See more on this below in the $().button(string)
documentation.
Single toggle
Add data-toggle="button"
to activate toggling on a single button.
Pre-toggled buttons need .active
and aria-pressed="true"
For pre-toggled buttons, you must add the .active
class and the aria-pressed="true"
attribute to the button
yourself.
Checkbox / Radio
Add data-toggle="buttons"
to a .btn-group
containing checkbox or radio inputs to enable toggling in their respective styles.
Preselected options need .active
For preselected options, you must add the .active
class to the input's label
yourself.
Visual checked state only updated on click
If the checked state of a checkbox button is updated without firing a click
event on the button (e.g. via <input type="reset">
or via setting the checked
property of the input), you will need to toggle the .active
class on the input's label
yourself.
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. This method is asynchronous and returns before the resetting has actually completed.
$().button(string)
Swaps text to any data defined text state.
Flexible plugin that utilizes a handful of classes for easy toggle behavior.
Plugin dependency
Collapse requires the transitions plugin to be included in your version of Bootstrap.
Example
Click the buttons below to show and hide another element via class changes:
-
.collapse
hides content -
.collapsing
is applied during transitions -
.collapse.in
shows content
You can use a link with the href
attribute, or a button with the data-target
attribute. In both cases, the data-toggle="collapse"
is required.
Link with href
Anim pariatur cliche reprehenderit, enim eiusmod high life accusamus terry richardson ad squid. Nihil anim keffiyeh helvetica, craft beer labore wes anderson cred nesciunt sapiente ea proident.
Accordion example
Extend the default collapse behavior to create an accordion with the panel component.
Collapsible Group Item #1
Anim pariatur cliche reprehenderit, enim eiusmod high life accusamus terry richardson ad squid. 3 wolf moon officia aute, non cupidatat skateboard dolor brunch. Food truck quinoa nesciunt laborum eiusmod. Brunch 3 wolf moon tempor, sunt aliqua put a bird on it squid single-origin coffee nulla assumenda shoreditch et. Nihil anim keffiyeh helvetica, craft beer labore wes anderson cred nesciunt sapiente ea proident. Ad vegan excepteur butcher vice lomo. Leggings occaecat craft beer farm-to-table, raw denim aesthetic synth nesciunt you probably haven't heard of them accusamus labore sustainable VHS.
Collapsible Group Item #2
Anim pariatur cliche reprehenderit, enim eiusmod high life accusamus terry richardson ad squid. 3 wolf moon officia aute, non cupidatat skateboard dolor brunch. Food truck quinoa nesciunt laborum eiusmod. Brunch 3 wolf moon tempor, sunt aliqua put a bird on it squid single-origin coffee nulla assumenda shoreditch et. Nihil anim keffiyeh helvetica, craft beer labore wes anderson cred nesciunt sapiente ea proident. Ad vegan excepteur butcher vice lomo. Leggings occaecat craft beer farm-to-table, raw denim aesthetic synth nesciunt you probably haven't heard of them accusamus labore sustainable VHS.
Collapsible Group Item #3
Anim pariatur cliche reprehenderit, enim eiusmod high life accusamus terry richardson ad squid. 3 wolf moon officia aute, non cupidatat skateboard dolor brunch. Food truck quinoa nesciunt laborum eiusmod. Brunch 3 wolf moon tempor, sunt aliqua put a bird on it squid single-origin coffee nulla assumenda shoreditch et. Nihil anim keffiyeh helvetica, craft beer labore wes anderson cred nesciunt sapiente ea proident. Ad vegan excepteur butcher vice lomo. Leggings occaecat craft beer farm-to-table, raw denim aesthetic synth nesciunt you probably haven't heard of them accusamus labore sustainable VHS.
It's also possible to swap out .panel-body
s with .list-group
s.
Collapsible list group
- Bootply
- One itmus ac facilin
- Second eros
Make expand/collapse controls accessible
Be sure to add aria-expanded
to the control element. This attribute explicitly defines the current state of the collapsible element to screen readers and similar assistive technologies. If the collapsible element is closed by default, it should have a value of aria-expanded="false"
. If you've set the collapsible element to be open by default using the in
class, set aria-expanded="true"
on the control instead. The plugin will automatically toggle this attribute based on whether or not the collapsible element has been opened or closed.
Additionally, if your control element is targeting a single collapsible element – i.e. the data-target
attribute is pointing to an id
selector – you may add an additional aria-controls
attribute to the control element, containing the id
of the collapsible element. Modern screen readers and similar assistive technologies make use of this attribute to provide users with additional shortcuts to navigate directly to the collapsible element itself.
Usage
The collapse plugin utilizes a few classes to handle the heavy lifting:
-
.collapse
hides the content -
.collapse.in
shows the content -
.collapsing
is added when the transition starts, and removed when it finishes
These classes can be found in component-animations.less
.
Via data attributes
Just add data-toggle="collapse"
and a data-target
to the element to automatically assign control of a collapsible element. The data-target
attribute accepts a CSS selector to apply the collapse to. Be sure to add the class collapse
to the collapsible element. If you'd like it to default open, add the additional class in
.
To add accordion-like group management to a collapsible control, add the data attribute data-parent="#selector"
. Refer to the demo to see this in action.
Via JavaScript
Enable manually with:
Options
Options can be passed via data attributes or JavaScript. For data attributes, append the option name to data-
, as in data-parent=""
.
Name | type | default | description |
---|---|---|---|
parent | selector | false | If a selector is provided, then all collapsible elements under the specified parent will be closed when this collapsible item is shown. (similar to traditional accordion behavior - this is dependent on the panel class) |
toggle | boolean | true | Toggles the collapsible element on invocation |
Methods
.collapse(options)
Activates your content as a collapsible element. Accepts an optional options object
.
.collapse('toggle')
Toggles a collapsible element to shown or hidden. Returns to the caller before the collapsible element has actually been shown or hidden (i.e. before the shown.bs.collapse
or hidden.bs.collapse
event occurs).
.collapse('show')
Shows a collapsible element. Returns to the caller before the collapsible element has actually been shown (i.e. before the shown.bs.collapse
event occurs).
.collapse('hide')
Hides a collapsible element. Returns to the caller before the collapsible element has actually been hidden (i.e. before the hidden.bs.collapse
event occurs).
Events
Bootstrap's collapse class exposes a few events for hooking into collapse functionality.
Event Type | Description |
---|---|
show.bs.collapse | This event fires immediately when the show instance method is called. |
shown.bs.collapse | This event is fired when a collapse element has been made visible to the user (will wait for CSS transitions to complete). |
hide.bs.collapse | This event is fired immediately when the hide method has been called. |
hidden.bs.collapse | This event is fired when a collapse element has been hidden from the user (will wait for CSS transitions to complete). |
A slideshow component for cycling through elements, like a carousel. Nested carousels are not supported.
Examples
Accessibility issue
The carousel component is generally not compliant with accessibility standards. If you need to be compliant, please consider other options for presenting your content.
Transition animations not supported in Internet Explorer 8 & 9
Bootstrap exclusively uses CSS3 for its animations, but Internet Explorer 8 & 9 don't support the necessary CSS properties. Thus, there are no slide transition animations when using these browsers. We have intentionally decided not to include jQuery-based fallbacks for the transitions.
Initial active element required
The .active
class needs to be added to one of the slides. Otherwise, the carousel will not be visible.
Glyphicon icons not necessary
The .glyphicon .glyphicon-chevron-left
and .glyphicon .glyphicon-chevron-right
classes are not necessarily needed for the controls. Bootstrap provides .icon-prev
and .icon-next
as plain unicode alternatives.
Optional captions
Add captions to your slides easily with the .carousel-caption
element within any .item
. Place just about any optional HTML within there and it will be automatically aligned and formatted.
Usage
Multiple carousels
Carousels require the use of an id
on the outermost container (the .carousel
) for carousel controls to function properly. When adding multiple carousels, or when changing a carousel's id
, be sure to update the relevant controls.
Via data attributes
Use data attributes to easily control the position of the carousel. data-slide
accepts the keywords prev
or next
, which alters the slide position relative to its current position. Alternatively, use data-slide-to
to pass a raw slide index to the carousel data-slide-to="2"
, which shifts the slide position to a particular index beginning with 0
.
The data-ride="carousel"
attribute is used to mark a carousel as animating starting at page load. It cannot be used in combination with (redundant and unnecessary) explicit JavaScript initialization of the same carousel.
Via JavaScript
Call carousel manually with:
Options
Options can be passed via data attributes or JavaScript. For data attributes, append the option name to data-
, as in data-interval=""
.
Name | type | default | description |
---|---|---|---|
interval | number | 5000 | The amount of time to delay between automatically cycling an item. If false, carousel will not automatically cycle. |
pause | string | null | "hover" | If set to "hover" , pauses the cycling of the carousel on mouseenter and resumes the cycling of the carousel on mouseleave . If set to null , hovering over the carousel won't pause it. |
wrap | boolean | true | Whether the carousel should cycle continuously or have hard stops. |
keyboard | boolean | true | Whether the carousel should react to keyboard events. |
Methods
.carousel(options)
Initializes the carousel with an optional options object
and starts cycling through items.
.carousel('cycle')
Cycles through the carousel items from left to right.
.carousel('pause')
Stops the carousel from cycling through items.
.carousel(number)
Cycles the carousel to a particular frame (0 based, similar to an array).
.carousel('prev')
Cycles to the previous item.
.carousel('next')
Cycles to the next item.
Events
Bootstrap's carousel class exposes two events for hooking into carousel functionality.
Both events have the following additional properties:
-
direction
: The direction in which the carousel is sliding (either"left"
or"right"
). -
relatedTarget
: The DOM element that is being slid into place as the active item.
All carousel events are fired at the carousel itself (i.e. at the <div class="carousel">
).
Event Type | Description |
---|---|
slide.bs.carousel | This event fires immediately when the slide instance method is invoked. |
slid.bs.carousel | This event is fired when the carousel has completed its slide transition. |
Example
The affix plugin toggles position: fixed;
on and off, emulating the effect found with position: sticky;
. The subnavigation on the right is a live demo of the affix plugin.
Usage
Use the affix plugin via data attributes or manually with your own JavaScript. In both situations, you must provide CSS for the positioning and width of your affixed content.
Note: Do not use the affix plugin on an element contained in a relatively positioned element, such as a pulled or pushed column, due to a Safari rendering bug.
Positioning via CSS
The affix plugin toggles between three classes, each representing a particular state: .affix
, .affix-top
, and .affix-bottom
. You must provide the styles, with the exception of position: fixed;
on .affix
, for these classes yourself (independent of this plugin) to handle the actual positions.
Here's how the affix plugin works:
- To start, the plugin adds
.affix-top
to indicate the element is in its top-most position. At this point no CSS positioning is required. - Scrolling past the element you want affixed should trigger the actual affixing. This is where
.affix
replaces.affix-top
and setsposition: fixed;
(provided by Bootstrap's CSS). - If a bottom offset is defined, scrolling past it should replace
.affix
with.affix-bottom
. Since offsets are optional, setting one requires you to set the appropriate CSS. In this case, addposition: absolute;
when necessary. The plugin uses the data attribute or JavaScript option to determine where to position the element from there.
Follow the above steps to set your CSS for either of the usage options below.
Via data attributes
To easily add affix behavior to any element, just add data-spy="affix"
to the element you want to spy on. Use offsets to define when to toggle the pinning of an element.
Via JavaScript
Call the affix plugin via JavaScript:
Options
Options can be passed via data attributes or JavaScript. For data attributes, append the option name to data-
, as in data-offset-top="200"
.
Name | type | default | description |
---|---|---|---|
offset | number | function | object | 10 | Pixels to offset from screen when calculating position of scroll. If a single number is provided, the offset will be applied in both top and bottom directions. To provide a unique, bottom and top offset just provide an object offset: { top: 10 } or offset: { top: 10, bottom: 5 } . Use a function when you need to dynamically calculate an offset. |
target | selector | node | jQuery element | the window object | Specifies the target element of the affix. |
Methods
.affix(options)
Activates your content as affixed content. Accepts an optional options object
.
.affix('checkPosition')
Recalculates the state of the affix based on the dimensions, position, and scroll position of the relevant elements. The .affix
, .affix-top
, and .affix-bottom
classes are added to or removed from the affixed content according to the new state. This method needs to be called whenever the dimensions of the affixed content or the target element are changed, to ensure correct positioning of the affixed content.
Events
Bootstrap's affix plugin exposes a few events for hooking into affix functionality.
Event Type | Description |
---|---|
affix.bs.affix | This event fires immediately before the element has been affixed. |
affixed.bs.affix | This event is fired after the element has been affixed. |
affix-top.bs.affix | This event fires immediately before the element has been affixed-top. |
affixed-top.bs.affix | This event is fired after the element has been affixed-top. |
affix-bottom.bs.affix | This event fires immediately before the element has been affixed-bottom. |
affixed-bottom.bs.affix | This event is fired after the element has been affixed-bottom. |
Source: https://getbootstrap.com/docs/3.3/javascript/
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