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diff --git a/site/docs/4.4/getting-started/javascript.md b/site/docs/4.4/getting-started/javascript.md new file mode 100644 index 0000000000..a509bd4826 --- /dev/null +++ b/site/docs/4.4/getting-started/javascript.md @@ -0,0 +1,211 @@ +--- +layout: docs +title: JavaScript +description: Bring Bootstrap to life with our optional JavaScript plugins built on jQuery. Learn about each plugin, our data and programmatic API options, and more. +group: getting-started +toc: true +--- + +## Individual or compiled + +Plugins can be included individually (using Bootstrap's individual `js/dist/*.js`), or all at once using `bootstrap.js` or the minified `bootstrap.min.js` (don't include both). + +If you use a bundler (Webpack, Rollup...), you can use `/js/dist/*.js` files which are UMD ready. + +## 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 `package.json`]({{ site.repo }}/blob/v{{ site.current_version }}/package.json) to see which versions of jQuery are supported. + +Our dropdowns, popovers and tooltips also depend on [Popper.js](https://popper.js.org/). + +## Data attributes + +Nearly all Bootstrap plugins can be enabled and configured through HTML alone with data attributes (our preferred way of using JavaScript functionality). Be sure to **only use one set of data attributes on a single element** (e.g., you cannot trigger a tooltip and modal from the same button.) + +However, in some situations it may be desirable to disable this functionality. To disable the data attribute API, unbind all events on the document namespaced with `data-api` like so: + +{% highlight js %} +$(document).off('.data-api') +{% endhighlight %} + +Alternatively, to target a specific plugin, just include the plugin's name as a namespace along with the data-api namespace like this: + +{% highlight js %} +$(document).off('.alert.data-api') +{% endhighlight %} + +{% capture callout %} +## Selectors + +Currently to query DOM elements we use the native methods `querySelector` and `querySelectorAll` for performance reasons, so you have to use [valid selectors](https://www.w3.org/TR/CSS21/syndata.html#value-def-identifier). +If you use special selectors, for example: `collapse:Example` be sure to escape them. +{% endcapture %} +{% include callout.html content=callout type="warning" %} + +## 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. + +All infinitive events provide [`preventDefault()`](https://developer.mozilla.org/en-US/docs/Web/API/Event/preventDefault) functionality. This provides the ability to stop the execution of an action before it starts. Returning false from an event handler will also automatically call `preventDefault()`. + +{% highlight js %} +$('#myModal').on('show.bs.modal', function (e) { + if (!data) { + return e.preventDefault() // stops modal from being shown + } +}) +{% endhighlight %} + +## Programmatic API + +We also believe you should be able to use all Bootstrap plugins purely through the JavaScript API. All public APIs are single, chainable methods, and return the collection acted upon. + +{% highlight js %} +$('.btn.danger').button('toggle').addClass('fat') +{% endhighlight %} + +All methods should accept an optional options object, a string which targets a particular method, or nothing (which initiates a plugin with default behavior): + +{% highlight js %} +$('#myModal').modal() // initialized with defaults +$('#myModal').modal({ keyboard: false }) // initialized with no keyboard +$('#myModal').modal('show') // initializes and invokes show immediately +{% endhighlight %} + +Each plugin also exposes its raw constructor on a `Constructor` property: `$.fn.popover.Constructor`. If you'd like to get a particular plugin instance, retrieve it directly from an element: `$('[rel="popover"]').data('popover')`. + +### Asynchronous functions and transitions + +All programmatic API methods are **asynchronous** and return to the caller once the transition is started but **before it ends**. + +In order to execute an action once the transition is complete, you can listen to the corresponding event. + +{% highlight js %} +$('#myCollapse').on('shown.bs.collapse', function (e) { + // Action to execute once the collapsible area is expanded +}) +{% endhighlight %} + +In addition a method call on a **transitioning component will be ignored**. + +{% highlight js %} +$('#myCarousel').on('slid.bs.carousel', function (e) { + $('#myCarousel').carousel('2') // Will slide to the slide 2 as soon as the transition to slide 1 is finished +}) + +$('#myCarousel').carousel('1') // Will start sliding to the slide 1 and returns to the caller +$('#myCarousel').carousel('2') // !! Will be ignored, as the transition to the slide 1 is not finished !! +{% endhighlight %} + +### Default settings + +You can change the default settings for a plugin by modifying the plugin's `Constructor.Default` object: + +{% highlight js %} +// changes default for the modal plugin's `keyboard` option to false +$.fn.modal.Constructor.Default.keyboard = false +{% endhighlight %} + +## 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. + +{% highlight js %} +var bootstrapButton = $.fn.button.noConflict() // return $.fn.button to previously assigned value +$.fn.bootstrapBtn = bootstrapButton // give $().bootstrapBtn the Bootstrap functionality +{% endhighlight %} + +## Version numbers + +The version of each of Bootstrap's jQuery plugins can be accessed via the `VERSION` property of the plugin's constructor. For example, for the tooltip plugin: + +{% highlight js %} +$.fn.tooltip.Constructor.VERSION // => "{{ site.current_version }}" +{% endhighlight %} + +## 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>`](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/noscript) to explain the situation (and how to re-enable JavaScript) to your users, and/or add your own custom fallbacks. + +{% capture callout %} +##### 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. +{% endcapture %} +{% include callout.html content=callout type="warning" %} + +## Util + +All Bootstrap's JavaScript files depend on `util.js` and it has to be included alongside the other JavaScript files. If you're using the compiled (or minified) `bootstrap.js`, there is no need to include this—it's already there. + +`util.js` includes utility functions and 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. + +## Sanitizer + +Tooltips and Popovers use our built-in sanitizer to sanitize options which accept HTML. + +The default `whiteList` value is the following: + +{% highlight js %} +var ARIA_ATTRIBUTE_PATTERN = /^aria-[\w-]*$/i +var DefaultWhitelist = { + // Global attributes allowed on any supplied element below. + '*': ['class', 'dir', 'id', 'lang', 'role', ARIA_ATTRIBUTE_PATTERN], + a: ['target', 'href', 'title', 'rel'], + area: [], + b: [], + br: [], + col: [], + code: [], + div: [], + em: [], + hr: [], + h1: [], + h2: [], + h3: [], + h4: [], + h5: [], + h6: [], + i: [], + img: ['src', 'alt', 'title', 'width', 'height'], + li: [], + ol: [], + p: [], + pre: [], + s: [], + small: [], + span: [], + sub: [], + sup: [], + strong: [], + u: [], + ul: [] +} +{% endhighlight %} + +If you want to add new values to this default `whiteList` you can do the following: + +{% highlight js %} +var myDefaultWhiteList = $.fn.tooltip.Constructor.Default.whiteList + +// To allow table elements +myDefaultWhiteList.table = [] + +// To allow td elements and data-option attributes on td elements +myDefaultWhiteList.td = ['data-option'] + +// You can push your custom regex to validate your attributes. +// Be careful about your regular expressions being too lax +var myCustomRegex = /^data-my-app-[\w-]+/ +myDefaultWhiteList['*'].push(myCustomRegex) +{% endhighlight %} + +If you want to bypass our sanitizer because you prefer to use a dedicated library, for example [DOMPurify](https://www.npmjs.com/package/dompurify), you should do the following: + +{% highlight js %} +$('#yourTooltip').tooltip({ + sanitizeFn: function (content) { + return DOMPurify.sanitize(content) + } +}) +{% endhighlight %} |