| commit | author | age | ||
| 83c3f6 | 1 | --- |
| SP | 2 | layout: docs |
| 3 | title: JavaScript | |
| 4 | 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. | |
| 5 | group: getting-started | |
| 6 | toc: true | |
| 7 | --- | |
| 8 | ||
| 9 | ## Individual or compiled | |
| 10 | ||
| 11 | 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). | |
| 12 | ||
| 13 | If you use a bundler (Webpack, Rollup...), you can use `/js/dist/*.js` files which are UMD ready. | |
| 14 | ||
| 15 | ## Dependencies | |
| 16 | ||
| 17 | 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. | |
| 18 | ||
| 19 | Our dropdowns, popovers and tooltips also depend on [Popper.js](https://popper.js.org/). | |
| 20 | ||
| 21 | ## Data attributes | |
| 22 | ||
| 23 | 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.) | |
| 24 | ||
| 25 | 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: | |
| 26 | ||
| 27 | {% highlight js %} | |
| 28 | $(document).off('.data-api') | |
| 29 | {% endhighlight %} | |
| 30 | ||
| 31 | Alternatively, to target a specific plugin, just include the plugin's name as a namespace along with the data-api namespace like this: | |
| 32 | ||
| 33 | {% highlight js %} | |
| 34 | $(document).off('.alert.data-api') | |
| 35 | {% endhighlight %} | |
| 36 | ||
| 37 | {% capture callout %} | |
| 38 | ## Selectors | |
| 39 | ||
| 40 | 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). | |
| 41 | If you use special selectors, for example: `collapse:Example` be sure to escape them. | |
| 42 | {% endcapture %} | |
| 43 | {% include callout.html content=callout type="warning" %} | |
| 44 | ||
| 45 | ## Events | |
| 46 | ||
| 47 | 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. | |
| 48 | ||
| 49 | 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()`. | |
| 50 | ||
| 51 | {% highlight js %} | |
| 52 | $('#myModal').on('show.bs.modal', function (e) { | |
| 53 | if (!data) return e.preventDefault() // stops modal from being shown | |
| 54 | }) | |
| 55 | {% endhighlight %} | |
| 56 | ||
| 57 | ## Programmatic API | |
| 58 | ||
| 59 | 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. | |
| 60 | ||
| 61 | {% highlight js %} | |
| 62 | $('.btn.danger').button('toggle').addClass('fat') | |
| 63 | {% endhighlight %} | |
| 64 | ||
| 65 | All methods should accept an optional options object, a string which targets a particular method, or nothing (which initiates a plugin with default behavior): | |
| 66 | ||
| 67 | {% highlight js %} | |
| 68 | $('#myModal').modal() // initialized with defaults | |
| 69 | $('#myModal').modal({ keyboard: false }) // initialized with no keyboard | |
| 70 | $('#myModal').modal('show') // initializes and invokes show immediately | |
| 71 | {% endhighlight %} | |
| 72 | ||
| 73 | Each plugin also exposes its raw constructor on a `Constructor` property: `$.fn.popover.Constructor`. If you'd like to get a particular plugin instance, retrieve it directly from an element: `$('[rel="popover"]').data('popover')`. | |
| 74 | ||
| 75 | ### Asynchronous functions and transitions | |
| 76 | ||
| 77 | All programmatic API methods are **asynchronous** and return to the caller once the transition is started but **before it ends**. | |
| 78 | ||
| 79 | In order to execute an action once the transition is complete, you can listen to the corresponding event. | |
| 80 | ||
| 81 | {% highlight js %} | |
| 82 | $('#myCollapse').on('shown.bs.collapse', function (e) { | |
| 83 | // Action to execute once the collapsible area is expanded | |
| 84 | }) | |
| 85 | {% endhighlight %} | |
| 86 | ||
| 87 | In addition a method call on a **transitioning component will be ignored**. | |
| 88 | ||
| 89 | {% highlight js %} | |
| 90 | $('#myCarousel').on('slid.bs.carousel', function (e) { | |
| 91 | $('#myCarousel').carousel('2') // Will slide to the slide 2 as soon as the transition to slide 1 is finished | |
| 92 | }) | |
| 93 | ||
| 94 | $('#myCarousel').carousel('1') // Will start sliding to the slide 1 and returns to the caller | |
| 95 | $('#myCarousel').carousel('2') // !! Will be ignored, as the transition to the slide 1 is not finished !! | |
| 96 | {% endhighlight %} | |
| 97 | ||
| 98 | ### Default settings | |
| 99 | ||
| 100 | You can change the default settings for a plugin by modifying the plugin's `Constructor.Default` object: | |
| 101 | ||
| 102 | {% highlight js %} | |
| 103 | $.fn.modal.Constructor.Default.keyboard = false // changes default for the modal plugin's `keyboard` option to false | |
| 104 | {% endhighlight %} | |
| 105 | ||
| 106 | ## No conflict | |
| 107 | ||
| 108 | 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. | |
| 109 | ||
| 110 | {% highlight js %} | |
| 111 | var bootstrapButton = $.fn.button.noConflict() // return $.fn.button to previously assigned value | |
| 112 | $.fn.bootstrapBtn = bootstrapButton // give $().bootstrapBtn the Bootstrap functionality | |
| 113 | {% endhighlight %} | |
| 114 | ||
| 115 | ## Version numbers | |
| 116 | ||
| 117 | 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: | |
| 118 | ||
| 119 | {% highlight js %} | |
| 120 | $.fn.tooltip.Constructor.VERSION // => "{{ site.current_version }}" | |
| 121 | {% endhighlight %} | |
| 122 | ||
| 123 | ## No special fallbacks when JavaScript is disabled | |
| 124 | ||
| 125 | 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. | |
| 126 | ||
| 127 | {% capture callout %} | |
| 128 | ##### Third-party libraries | |
| 129 | ||
| 130 | **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. | |
| 131 | {% endcapture %} | |
| 132 | {% include callout.html content=callout type="warning" %} | |
| 133 | ||
| 134 | ## Util | |
| 135 | ||
| 136 | 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. | |
| 137 | ||
| 138 | `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. | |