From 2e3b5c88fce6cc630ff1b6e7c3a0b702e7b0d1a9 Mon Sep 17 00:00:00 2001 From: Hakim El Hattab Date: Thu, 7 May 2020 11:40:05 +0200 Subject: [PATCH 1/2] move docs to revealjs.com --- README.md | 1475 +---------------------------------------------------- 1 file changed, 5 insertions(+), 1470 deletions(-) diff --git a/README.md b/README.md index 1f1f83e..348d65b 100644 --- a/README.md +++ b/README.md @@ -1,1479 +1,14 @@ # reveal.js ![tests](https://github.com/hakimel/reveal.js/workflows/tests/badge.svg) Slides -A framework for easily creating beautiful presentations using HTML. [Check out the live demo](https://revealjs.com/). +reveal.js is an open source HTML presentation framework. It's a tool that enables anyone with a web browser to create fully featured and beautiful presentations for free. [Check out the live demo](https://revealjs.com/). -reveal.js comes with a broad range of features including [nested slides](https://github.com/hakimel/reveal.js#markup), [Markdown support](https://github.com/hakimel/reveal.js#markdown), [PDF export](https://github.com/hakimel/reveal.js#pdf-export), [speaker notes](https://github.com/hakimel/reveal.js#speaker-notes) and a [JavaScript API](https://github.com/hakimel/reveal.js#api). There's also a fully featured visual editor and platform for sharing reveal.js presentations at [slides.com](https://slides.com?ref=github). +---- -### Supporting reveal.js -This project was started and is maintained by [@hakimel](https://github.com/hakimel/) with the help of many [contributions from the community](https://github.com/hakimel/reveal.js/graphs/contributors). The best way to support the project is to [become a paying member of Slides.com](https://slides.com/pricing)—the reveal.js presentation platform that Hakim is building. - - -## Table of contents - -- [Online Editor](#online-editor) -- [Installation](#installation) - - [Basic setup](#basic-setup) - - [Full setup](#full-setup) -- [Markup](#markup) -- [Initialization](#initialization) -- [Configuration](#configuration) -- [Presentation Size](#presentation-size) -- [Ready Event](#ready-event) -- [Auto-Slide](#auto-slide) -- [Auto-Animate](#auto-animate) -- [Keyboard Bindings](#keyboard-bindings) -- [Vertical Slide Navigation](#vertical-slide-navigation) -- [Touch Navigation](#touch-navigation) -- [Lazy Loading](#lazy-loading) -- [Plugins](#plugins) -- [Dependencies](#dependencies) -- [API](#api) - - [Custom Key Bindings](#custom-key-bindings) - - [Slide Change Events](#slide-change-events) - - [Presentation State](#presentation-state) - - [Slide States](#slide-states) - - [Slide Backgrounds](#slide-backgrounds) - - [Parallax Background](#parallax-background) - - [Slide Transitions](#slide-transitions) - - [Internal links](#internal-links) - - [Fragments](#fragments) - - [Fragment events](#fragment-events) - - [Code syntax highlighting](#code-syntax-highlighting) - - [Slide number](#slide-number) - - [Overview mode](#overview-mode) - - [Fullscreen mode](#fullscreen-mode) - - [Embedded media](#embedded-media) - - [Stretching elements](#stretching-elements) - - [Resize Event](#resize-event) - - [postMessage API](#postmessage-api) -- [Markdown](#markdown) - - [External Markdown](#external-markdown) - - [Element Attributes](#element-attributes) - - [Slide Attributes](#slide-attributes) -- [PDF Export](#pdf-export) -- [Theming](#theming) -- [Speaker Notes](#speaker-notes) - - [Share and Print Speaker Notes](#share-and-print-speaker-notes) - - [Server Side Speaker Notes](#server-side-speaker-notes) -- [Multiplexing](#multiplexing) -- [MathJax](#mathjax) -- [License](#license) - -#### More reading - -- [Changelog](https://github.com/hakimel/reveal.js/releases): Up-to-date version history. -- [Examples](https://github.com/hakimel/reveal.js/wiki/Example-Presentations): Presentations created with reveal.js, add your own! -- [Browser Support](https://github.com/hakimel/reveal.js/wiki/Browser-Support): Explanation of browser support and fallbacks. -- [Plugins](https://github.com/hakimel/reveal.js/wiki/Plugins,-Tools-and-Hardware): A list of plugins that can be used to extend reveal.js. - - -## Online Editor - -Presentations are written using HTML or Markdown but there's also an online editor for those of you who prefer a graphical interface. Give it a try at [https://slides.com](https://slides.com?ref=github). - - -## Installation - -The **basic setup** is for authoring presentations only. The **full setup** gives you access to all reveal.js features and plugins such as speaker notes as well as the development tasks needed to make changes to the source. - -### Basic setup - -The core of reveal.js is very easy to install. You'll simply need to download a copy of this repository and open the index.html file directly in your browser. - -1. Download the latest version of reveal.js from -2. Unzip and replace the example contents in index.html with your own -3. Open index.html in a browser to view it - -### Full setup - -Some reveal.js features, like external Markdown and speaker notes, require that presentations run from a local web server. The following instructions will set up such a server as well as all of the development tasks needed to make edits to the reveal.js source code. - -1. Install [Node.js](https://nodejs.org/) (10.0.0 or later) - -1. Clone the reveal.js repository - ```sh - $ git clone https://github.com/hakimel/reveal.js.git - ``` - -1. Move to the reveal.js folder and install dependencies - ```sh - $ cd reveal.js && npm install - ``` - -1. Serve the presentation and monitor source files for changes - ```sh - $ npm start - ``` - -1. Open to view your presentation - - You can change the port by using `npm start -- --port=8001`. - -## Markup - -Here's a barebones example of a fully working reveal.js presentation: -```html - - - - - - -
-
-
Slide 1
-
Slide 2
-
-
- - - - -``` - -The presentation markup hierarchy needs to be `.reveal > .slides > section` where the `section` represents one slide and can be repeated indefinitely. If you place multiple `section` elements inside of another `section` they will be shown as vertical slides. The first of the vertical slides is the "root" of the others (at the top), and will be included in the horizontal sequence. For example: - -```html -
-
-
Single Horizontal Slide
-
-
Vertical Slide 1
-
Vertical Slide 2
-
-
-
-``` - -It's also possible to write presentations using [Markdown](#markdown). - -### Initialization - -If you only have a single presentation on the page we recommend initializing reveal.js using the singleton API. -```html - - -``` - -The `initialize` method returns a promise which will resolve as soon as the presentation is ready and can be interacted with via the API. -```js -Reveal.initialize.then( () => { - // reveal.js is ready -} ) -``` - -If you want to run multiple presentations side-by-side on the same page you can create instances of the Reveal class. Note that you will also need to set the `embedded` config option to true. -```html -
...
-
...
- - -``` - -### ES Module - -We provide two JavaScript bundles; `/dist/reveal.es5.js` with support for legacy browers and `/dist/reveal.js` which targets modern browsers with ES6 support. - -Here's how to import and initialize the ES module version of reveal.js, including the Markdown plugin: - -```html - -``` - -### Configuration - -At the end of your page you need to initialize reveal by running the following code. Note that all configuration values are optional and will default to the values specified below. - -```javascript -Reveal.initialize({ - - // Display presentation control arrows - controls: true, - - // Help the user learn the controls by providing hints, for example by - // bouncing the down arrow when they first encounter a vertical slide - controlsTutorial: true, - - // Determines where controls appear, "edges" or "bottom-right" - controlsLayout: 'bottom-right', - - // Visibility rule for backwards navigation arrows; "faded", "hidden" - // or "visible" - controlsBackArrows: 'faded', - - // Display a presentation progress bar - progress: true, - - // Display the page number of the current slide - slideNumber: false, - - // Add the current slide number to the URL hash so that reloading the - // page/copying the URL will return you to the same slide - hash: false, - - // Push each slide change to the browser history. Implies `hash: true` - history: false, - - // Enable keyboard shortcuts for navigation - keyboard: true, - - // Enable the slide overview mode - overview: true, - - // Vertical centering of slides - center: true, - - // Enables touch navigation on devices with touch input - touch: true, - - // Loop the presentation - loop: false, - - // Change the presentation direction to be RTL - rtl: false, - - // See https://github.com/hakimel/reveal.js/#navigation-mode - navigationMode: 'default', - - // Randomizes the order of slides each time the presentation loads - shuffle: false, - - // Turns fragments on and off globally - fragments: true, - - // Flags whether to include the current fragment in the URL, - // so that reloading brings you to the same fragment position - fragmentInURL: true, - - // Flags if the presentation is running in an embedded mode, - // i.e. contained within a limited portion of the screen - embedded: false, - - // Flags if we should show a help overlay when the questionmark - // key is pressed - help: true, - - // Flags if speaker notes should be visible to all viewers - showNotes: false, - - // Global override for autoplaying embedded media (video/audio/iframe) - // - null: Media will only autoplay if data-autoplay is present - // - true: All media will autoplay, regardless of individual setting - // - false: No media will autoplay, regardless of individual setting - autoPlayMedia: null, - - // Global override for preloading lazy-loaded iframes - // - null: Iframes with data-src AND data-preload will be loaded when within - // the viewDistance, iframes with only data-src will be loaded when visible - // - true: All iframes with data-src will be loaded when within the viewDistance - // - false: All iframes with data-src will be loaded only when visible - preloadIframes: null, - - // Can be used to globally disable auto-animation - autoAnimate: true, - - // Optionally provide a custom element matcher that will be - // used to dictate which elements we can animate between. - autoAnimateMatcher: null, - - // Default settings for our auto-animate transitions, can be - // overridden per-slide or per-element via data arguments - autoAnimateEasing: 'ease', - autoAnimateDuration: 1.0, - autoAnimateUnmatched: true, - - // CSS properties that can be auto-animated. Position & scale - // is matched separately so there's no need to include styles - // like top/right/bottom/left, width/height or margin. - autoAnimateStyles: [ - 'opacity', - 'color', - 'background-color', - 'padding', - 'font-size', - 'line-height', - 'letter-spacing', - 'border-width', - 'border-color', - 'border-radius', - 'outline', - 'outline-offset' - ], - - // Number of milliseconds between automatically proceeding to the - // next slide, disabled when set to 0, this value can be overwritten - // by using a data-autoslide attribute on your slides - autoSlide: 0, - - // Stop auto-sliding after user input - autoSlideStoppable: true, - - // Use this method for navigation when auto-sliding - autoSlideMethod: Reveal.next, - - // Specify the average time in seconds that you think you will spend - // presenting each slide. This is used to show a pacing timer in the - // speaker view - defaultTiming: 120, - - // Specify the total time in seconds that is available to - // present. If this is set to a nonzero value, the pacing - // timer will work out the time available for each slide, - // instead of using the defaultTiming value - totalTime: 0, - - // Specify the minimum amount of time you want to allot to - // each slide, if using the totalTime calculation method. If - // the automated time allocation causes slide pacing to fall - // below this threshold, then you will see an alert in the - // speaker notes window - minimumTimePerSlide: 0, - - // Enable slide navigation via mouse wheel - mouseWheel: false, - - // Hide cursor if inactive - hideInactiveCursor: true, - - // Time before the cursor is hidden (in ms) - hideCursorTime: 5000, - - // Opens links in an iframe preview overlay - // Add `data-preview-link` and `data-preview-link="false"` to customise each link - // individually - previewLinks: false, - - // Transition style - transition: 'slide', // none/fade/slide/convex/concave/zoom - - // Transition speed - transitionSpeed: 'default', // default/fast/slow - - // Transition style for full page slide backgrounds - backgroundTransition: 'fade', // none/fade/slide/convex/concave/zoom - - // Number of slides away from the current that are visible - viewDistance: 3, - - // Number of slides away from the current that are visible on mobile - // devices. It is advisable to set this to a lower number than - // viewDistance in order to save resources. - mobileViewDistance: 2, - - // Parallax background image - parallaxBackgroundImage: '', // e.g. "'https://s3.amazonaws.com/hakim-static/reveal-js/reveal-parallax-1.jpg'" - - // Parallax background size - parallaxBackgroundSize: '', // CSS syntax, e.g. "2100px 900px" - - // Number of pixels to move the parallax background per slide - // - Calculated automatically unless specified - // - Set to 0 to disable movement along an axis - parallaxBackgroundHorizontal: null, - parallaxBackgroundVertical: null, - - // The display mode that will be used to show slides - display: 'block' - -}); -``` - -The configuration can be updated after initialization using the `configure` method: - -```javascript -// Turn autoSlide off -Reveal.configure({ autoSlide: 0 }); - -// Start auto-sliding every 5s -Reveal.configure({ autoSlide: 5000 }); -``` - -### Presentation Size - -All presentations have a normal size, that is, the resolution at which they are authored. The framework will automatically scale presentations uniformly based on this size to ensure that everything fits on any given display or viewport. - -See below for a list of configuration options related to sizing, including default values: - -```javascript -Reveal.initialize({ - - // ... - - // The "normal" size of the presentation, aspect ratio will be preserved - // when the presentation is scaled to fit different resolutions. Can be - // specified using percentage units. - width: 960, - height: 700, - - // Factor of the display size that should remain empty around the content - margin: 0.1, - - // Bounds for smallest/largest possible scale to apply to content - minScale: 0.2, - maxScale: 1.5 - -}); -``` - -If you wish to disable this behavior and do your own scaling (e.g. using media queries), try these settings: - -```javascript -Reveal.initialize({ - - // ... - - width: "100%", - height: "100%", - margin: 0, - minScale: 1, - maxScale: 1 -}); -``` - -### Ready Event - -A `ready` event is fired when reveal.js has loaded all non-async dependencies and is ready to start navigating. To check if reveal.js is already 'ready' you can call `Reveal.isReady()`. - -```javascript -Reveal.on( 'ready', event => { - // event.currentSlide, event.indexh, event.indexv -} ); -``` - -Note that we also add a `.ready` class to the `.reveal` element so that you can hook into this with CSS. - -### Auto-Slide - -Presentations can be configured to progress through slides automatically, without any user input. To enable this you will need to tell the framework how many milliseconds it should wait between slides: - -```javascript -// Slide every five seconds -Reveal.configure({ - autoSlide: 5000 -}); -``` - -When this is turned on a control element will appear that enables users to pause and resume auto-sliding. Alternatively, sliding can be paused or resumed by pressing »A« on the keyboard. Sliding is paused automatically as soon as the user starts navigating. You can disable these controls by specifying `autoSlideStoppable: false` in your reveal.js config. - -You can also override the slide duration for individual slides and fragments by using the `data-autoslide` attribute: - -```html -
-

After 2 seconds the first fragment will be shown.

-

After 10 seconds the next fragment will be shown.

-

Now, the fragment is displayed for 2 seconds before the next slide is shown.

-
-``` - -To override the method used for navigation when auto-sliding, you can specify the `autoSlideMethod` setting. To only navigate along the top layer and ignore vertical slides, set this to `Reveal.navigateRight`. - -Whenever the auto-slide mode is resumed or paused the `autoslideresumed` and `autoslidepaused` events are fired. - -### Keyboard Bindings - -If you're unhappy with any of the default keyboard bindings you can override them using the `keyboard` config option: - -```javascript -Reveal.configure({ - keyboard: { - 13: 'next', // go to the next slide when the ENTER key is pressed - 27: () => { console.log('esc') }, // do something custom when ESC is pressed - 32: null // don't do anything when SPACE is pressed (i.e. disable a reveal.js default binding) - } -}); -``` - -### Auto-Animate - -reveal.js can automatically animate elements across slides. All you need to do is add `data-auto-animate` to two adjacent slide `
` elements and Auto-Animate will animate all matching elements between the two. - -Here's a simple example to give you a better idea of how it can be used. The resulting animation will be the word "Magic" sliding 100px downwards. -```html -
-

Magic

-
-
-

Magic

-
-``` - -This example uses the `top` property to move the element but internally reveal.js will use a CSS transform to ensure smooth movement. This same approach to animation works with most animatable CSS properties meaning you can transition things like `position`, `font-size`, `line-height`, `color`, `background-color` and `padding`. - -#### How Elements are Matched -When you navigate between two auto-animated slides we'll do our best to automatically find matching elements between the two slides. For text, we consider it a match if both the text contents and node type are identical. For images, videos and iframes we compare the `src` attribute. We also take into account the order in which the element appears in the DOM. - -In situations where automatic matching is not feasible you can give the objects that you want to animate between a matching `data-id` attribute. We prioritize matching `data-id` values above our automatic matching. - -Here's an example where we've given both blocks a matching ID since automatic matching has no content to go on. - -```html -
-
-
-
-
-
-``` - -#### Animation Settings -You can override specific animation settings such as easing and duration either for the whole presentation, per-slide or individually for each animated element. The following configuration attributes can be used to change the settings for a specific slide or element: - -| Attribute                                              | Default | Description -| :------------------------------- | ---------: | :---------- -| data-auto-animate-easing | ease | A CSS [easing function](https://developer.mozilla.org/en-US/docs/Web/CSS/easing-function). -| data-auto-animate-unmatched | true | Determines whether elements with no matching auto-animate target should fade in. Set to false to make them appear instantly. -| data-auto-animate-duration | 1.0 | Animation duration in seconds. -| data-auto-animate-delay | 0 | Animation delay in seconds (can only be set for specific elements, not at the slide level). - -If you'd like to change the defaults for the whole deck, use the following config options: -```javascript -Reveal.initialize({ - autoAnimateEasing: 'ease-out', - autoAnimateDuration: 0.8, - autoAnimateUnmatched: false -}) -``` - -#### API: State Attributes and Events -We add state attributes to the different elements involved in an auto-animation. These attributes can be tied into if you want to, for example, fine-tune the animation behavior with custom CSS. - -Right before an auto-animation starts we add `data-auto-animate="pending"` to the slide `
`. At this point the upcoming slide is visible and all of the animated elements have been moved to their starting positions. Next we switch to `data-auto-animate="running"` to indicate when the elements start animating towards their final properties. - -Each individual element is decorated with a `data-auto-animate-target` attribute. The value of the attribute is a unique ID for this particular animation OR "unmatched" if this element should animate as unmatched content. - -Each time a presentation navigates between two auto-animated slides it dispatches the `autoanimate` event. -```javascript -Reveal.on( 'autoanimate', event => { - // event.fromSlide, event.toSlide -} ); -``` - -### Vertical Slide Navigation - -Slides can be nested within other slides to create vertical stacks (see [Markup](#markup)). When presenting, you use the left/right arrows to step through the main (horizontal) slides. When you arrive at a vertical stack you can optionally press the up/down arrows to view the vertical slides or skip past them by pressing the right arrow. Here's an example showing a bird's-eye view of what this looks like in action: - - - -#### Navigation Mode -You can fine tune the reveal.js navigation behavior by using the `navigationMode` config option. Note that these options are only useful for presentations that use a mix of horizontal and vertical slides. The following navigation modes are available: - -| Value | Description | -| :--------------------------- | :---------- | -| default | Left/right arrow keys step between horizontal slides. Up/down arrow keys step between vertical slides. Space key steps through all slides (both horizontal and vertical). | -| linear | Removes the up/down arrows. Left/right arrows step through all slides (both horizontal and vertical). | -| grid | When this is enabled, stepping left/right from a vertical stack to an adjacent vertical stack will land you at the same vertical index.

Consider a deck with six slides ordered in two vertical stacks:
`1.1`    `2.1`
`1.2`    `2.2`
`1.3`    `2.3`

If you're on slide 1.3 and navigate right, you will normally move from 1.3 -> 2.1. With navigationMode set to "grid" the same navigation takes you from 1.3 -> 2.3. | - -### Touch Navigation - -You can swipe to navigate through a presentation on any touch-enabled device. Horizontal swipes change between horizontal slides, vertical swipes change between vertical slides. If you wish to disable this you can set the `touch` config option to false when initializing reveal.js. - -If there's some part of your content that needs to remain accessible to touch events you'll need to highlight this by adding a `data-prevent-swipe` attribute to the element. One common example where this is useful is elements that need to be scrolled. - -### Lazy Loading - -When working on presentation with a lot of media or iframe content it's important to load lazily. Lazy loading means that reveal.js will only load content for the few slides nearest to the current slide. The number of slides that are preloaded is determined by the `viewDistance` configuration option. - -To enable lazy loading all you need to do is change your `src` attributes to `data-src` as shown below. This is supported for image, video, audio and iframe elements. - -```html -
- - - -
-``` - -#### Lazy Loading Iframes - -Note that lazy loaded iframes ignore the `viewDistance` configuration and will only load when their containing slide becomes visible. Iframes are also unloaded as soon as the slide is hidden. - -When we lazy load a video or audio element, reveal.js won't start playing that content until the slide becomes visible. However there is no way to control this for an iframe since that could contain any kind of content. That means if we loaded an iframe before the slide is visible on screen it could begin playing media and sound in the background. - -You can override this behavior with the `data-preload` attribute. The iframe below will be loaded -according to the `viewDistance`. - -```html -
- -
-``` - -You can also change the default globally with the `preloadIframes` configuration option. If set to -`true` ALL iframes with a `data-src` attribute will be preloaded when within the `viewDistance` -regardless of individual `data-preload` attributes. If set to `false`, all iframes will only be -loaded when they become visible. - -### Plugins - -**Outdated, this will be rewritten to match the 4.0 plugin API** - -Plugins should register themselves with reveal.js by calling `Reveal.registerPlugin( MyPlugin )`. Registered plugins _must_ expose a unique `id` property and can optionally expose an `init` function that reveal.js will call to initialize them. - -When reveal.js is booted up via `initialize()`, it will go through all registered plugins and invoke their `init` methods. If the `init` method returns a Promise, reveal.js will wait for that promise to be fulfilled before finishing the startup sequence and firing the [ready](#ready-event) event. Here’s an example of a plugin that does some asynchronous work before reveal.js can proceed: - -```javascript -let MyPlugin = { - id: ’my-plugin’, - init: deck => { - return new Promise( resolve => setTimeout( resolve, 3000 ) ) - } -}; -Reveal.initialize({ - plugins: [ MyPlugin ] -}).then( () => { - console.log( ’Three seconds later...’ ) -} ); -``` - -If the plugin’s init method does _not_ return a Promise, the plugin is considered ready right away and will not hold up the reveal.js startup sequence. - -### Manually Registering Plugins - -TBD. Describe how plugins can be registered after reveal.js is already initialized. - -### Retrieving Plugins - -If you want to check if a specific plugin is registered you can use the `Reveal.hasPlugin` method and pass in a plugin ID, for example: `Reveal.hasPlugin( ’my-plugin’ )`. If you want to retrieve a plugin instance you can use `Reveal.getPlugin( ’my-plugin’ )`. - -### Dependencies - -Reveal.js doesn’t _rely_ on any third party scripts to work but a few optional libraries are included by default. These libraries are loaded as dependencies in the order they appear, for example: - -```javascript -Reveal.initialize({ - dependencies: [ - // Interpret Markdown in
elements - { src: ’plugin/markdown/marked.js’, condition: () => { return !!document.querySelector( ’[data-markdown]’ ); } }, - { src: ’plugin/markdown/markdown.js’, condition: () => { return !!document.querySelector( ’[data-markdown]’ ); } }, - - // Syntax highlight for elements - { src: ’plugin/highlight/highlight.js’, async: true }, - - // Zoom in and out with Alt+click - { src: ’plugin/zoom-js/zoom.js’, async: true }, - - // Speaker notes - { src: ’plugin/notes/notes.js’, async: true }, - - // MathJax - { src: ’plugin/math/math.js’, async: true } - ] -}); -``` - -You can add your own extensions using the same syntax. The following properties are available for each dependency object: -- **src**: Path to the script to load -- **async**: [optional] Flags if the script should load after reveal.js has started, defaults to false -- **callback**: [optional] Function to execute when the script has loaded -- **condition**: [optional] Function which must return true for the script to be loaded - -You can also include dependencies which are bundled/already present on the page. To include a bundled plugin. replace the `src` property with a reference to a `plugin` instance: -- **plugin**: the plugin instance (see [Plugins](#plugins)) - -### API - -The `Reveal` object exposes a JavaScript API for controlling navigation and reading state: - -```javascript -// Navigation -Reveal.slide( indexh, indexv, indexf ); -Reveal.left(); -Reveal.right(); -Reveal.up(); -Reveal.down(); -Reveal.prev(); -Reveal.next(); -Reveal.prevFragment(); -Reveal.nextFragment(); - -// Randomize the order of slides -Reveal.shuffle(); - -// Toggle presentation states, optionally pass true/false to force on/off -Reveal.toggleOverview(); -Reveal.togglePause(); -Reveal.toggleAutoSlide(); - -// Shows a help overlay with keyboard shortcuts, optionally pass true/false -// to force on/off -Reveal.toggleHelp(); - -// Change a config value at runtime -Reveal.configure({ controls: true }); - -// Returns the present configuration options -Reveal.getConfig(); - -// Fetch the current scale of the presentation -Reveal.getScale(); - -Reveal.getComputedSlideSize(); // Returns object with width, height keys, and (scaled) presentationWidth and presentationHeight. - -// Retrieves the previous and current slide elements -Reveal.getPreviousSlide(); -Reveal.getCurrentSlide(); - -Reveal.getIndices(); // { h: 0, v: 0, f: 0 } -Reveal.getSlidePastCount(); -Reveal.getProgress(); // (0 == first slide, 1 == last slide) -Reveal.getSlides(); // Array of all slides -Reveal.getTotalSlides(); // Total number of slides - -// Returns an array with all horizontal/vertical slides in the deck -Reveal.getHorizontalSlides(); -Reveal.getVerticalSlides(); - -// Checks if the presentation contains two or more -// horizontal/vertical slides -Reveal.hasHorizontalSlides(); -Reveal.hasVerticalSlides(); - -// Returns the speaker notes for the current slide -Reveal.getSlideNotes(); - -// State checks -Reveal.isFirstSlide(); -Reveal.isLastSlide(); -Reveal.isOverview(); -Reveal.isPaused(); -Reveal.isAutoSliding(); - -// Returns the top-level DOM element -Reveal.getRevealElement(); //
...
-``` - -### Custom Key Bindings - -Custom key bindings can be added and removed using the following Javascript API. Custom key bindings will override the default keyboard bindings, but will in turn be overridden by the user defined bindings in the ``keyboard`` config option. - -```javascript -Reveal.addKeyBinding( binding, callback ); -Reveal.removeKeyBinding( keyCode ); -``` - -For example - -```javascript -// The binding parameter provides the following properties -// keyCode: the keycode for binding to the callback -// key: the key label to show in the help overlay -// description: the description of the action to show in the help overlay -Reveal.addKeyBinding( { keyCode: 84, key: 'T', description: 'Start timer' }, () => { - // start timer -} ) - -// The binding parameter can also be a direct keycode without providing the help description -Reveal.addKeyBinding( 82, () => { - // reset timer -} ) -``` - -This allows plugins to add key bindings directly to Reveal so they can - -* make use of Reveal's pre-processing logic for key handling (for example, ignoring key presses when paused); and -* be included in the help overlay (optional) - -### Slide Change Events - -A `slidechanged` event is fired each time the slide is changed. The event object holds the index values of the current slide as well as a reference to the previous and current slide DOM nodes. - -Some libraries, like MathJax (see [#226](https://github.com/hakimel/reveal.js/issues/226#issuecomment-10261609)), get confused by the transforms and display states of slides. Often times, this can be fixed by calling their update or render function from this callback. - -```javascript -Reveal.on( 'slidechanged', event => { - // event.previousSlide, event.currentSlide, event.indexh, event.indexv -} ); -``` - -The `slidechanged` event fires instantly when the slide changes. If you'd rather invoke your event listener when the slide has finished transitioning and is fully visible, you can use the `slidetransitionend` event. The `slidetransitionend` event includes the same event data as described above. - -```javascript -Reveal.on( 'slidetransitionend', event => console.log( event.currentSlide ) ); -``` - -### Presentation State - -The presentation's current state can be fetched by using the `getState` method. A state object contains all of the information required to put the presentation back as it was when `getState` was first called. Sort of like a snapshot. It's a simple object that can easily be stringified and persisted or sent over the wire. - -```javascript -Reveal.slide( 1 ); -// we're on slide 1 - -var state = Reveal.getState(); - -Reveal.slide( 3 ); -// we're on slide 3 - -Reveal.setState( state ); -// we're back on slide 1 -``` - -### Slide States - -If you set `data-state="somestate"` on a slide `
`, "somestate" will be applied as a class on the document element when that slide is opened. This allows you to apply broad style changes to the page based on the active slide. - -Furthermore you can also listen to these changes in state via JavaScript: - -```javascript -Reveal.on( 'somestate', () => { - // TODO: Sprinkle magic -}, false ); -``` - -### Slide Visibility -When preparing a presentation it can sometimes be helpful to prepare optional slides that you may or may not have time to show. This is easily done by appending a few slides at the end of the presentation, however this means that the reveal.js progress bar and slide numbering will hint that there are additional slides. - -To "hide" those slides from reveal.js' numbering system you can add a `data-visibility` attribute to the slide like so `
`. - -### Slide Backgrounds - -Slides are contained within a limited portion of the screen by default to allow them to fit any display and scale uniformly. You can apply full page backgrounds outside of the slide area by adding a `data-background` attribute to your `
` elements. Four different types of backgrounds are supported: color, image, video and iframe. - -#### Color Backgrounds - -All CSS color formats are supported, including hex values, keywords, `rgba()` or `hsl()`. - -```html -
-

Color

-
-``` - -#### Image Backgrounds - -By default, background images are resized to cover the full page. Available options: - -| Attribute | Default | Description | -| :------------------------------- | :--------- | :---------- | -| data-background-image | | URL of the image to show. GIFs restart when the slide opens. | -| data-background-size | cover | See [background-size](https://developer.mozilla.org/docs/Web/CSS/background-size) on MDN. | -| data-background-position | center | See [background-position](https://developer.mozilla.org/docs/Web/CSS/background-position) on MDN. | -| data-background-repeat | no-repeat | See [background-repeat](https://developer.mozilla.org/docs/Web/CSS/background-repeat) on MDN. | -| data-background-opacity | 1 | Opacity of the background image on a 0-1 scale. 0 is transparent and 1 is fully opaque. | - -```html -
-

Image

-
-
-

This background image will be sized to 100px and repeated

-
-``` - -#### Video Backgrounds - -Automatically plays a full size video behind the slide. - -| Attribute | Default | Description | -| :--------------------------- | :------ | :---------- | -| data-background-video | | A single video source, or a comma separated list of video sources. | -| data-background-video-loop | false | Flags if the video should play repeatedly. | -| data-background-video-muted | false | Flags if the audio should be muted. | -| data-background-size | cover | Use `cover` for full screen and some cropping or `contain` for letterboxing. | -| data-background-opacity | 1 | Opacity of the background video on a 0-1 scale. 0 is transparent and 1 is fully opaque. | - -```html -
-

Video

-
-``` - -#### Iframe Backgrounds - -Embeds a web page as a slide background that covers 100% of the reveal.js width and height. The iframe is in the background layer, behind your slides, and as such it's not possible to interact with it by default. To make your background interactive, you can add the `data-background-interactive` attribute. - -```html -
-

Iframe

-
-``` - -Iframes are lazy-loaded when they become visible. If you'd like to preload iframes ahead of time, you can append a `data-preload` attribute to the slide `
`. You can also enable preloading globally for all iframes using the `preloadIframes` configuration option. - -#### Background Transitions - -Backgrounds transition using a fade animation by default. This can be changed to a linear sliding transition by passing `backgroundTransition: 'slide'` to the `Reveal.initialize()` call. Alternatively you can set `data-background-transition` on any section with a background to override that specific transition. - - -### Parallax Background - -If you want to use a parallax scrolling background, set the first two properties below when initializing reveal.js (the other two are optional). - -```javascript -Reveal.initialize({ - - // Parallax background image - parallaxBackgroundImage: '', // e.g. "https://s3.amazonaws.com/hakim-static/reveal-js/reveal-parallax-1.jpg" - - // Parallax background size - parallaxBackgroundSize: '', // CSS syntax, e.g. "2100px 900px" - currently only pixels are supported (don't use % or auto) - - // Number of pixels to move the parallax background per slide - // - Calculated automatically unless specified - // - Set to 0 to disable movement along an axis - parallaxBackgroundHorizontal: 200, - parallaxBackgroundVertical: 50 - -}); -``` - -Make sure that the background size is much bigger than screen size to allow for some scrolling. [View example](http://revealjs.com/?parallaxBackgroundImage=https%3A%2F%2Fs3.amazonaws.com%2Fhakim-static%2Freveal-js%2Freveal-parallax-1.jpg¶llaxBackgroundSize=2100px%20900px). - -### Slide Transitions - -The global presentation transition is set using the `transition` config value. You can override the global transition for a specific slide by using the `data-transition` attribute: - -```html -
-

This slide will override the presentation transition and zoom!

-
- -
-

Choose from three transition speeds: default, fast or slow!

-
-``` - -You can also use different in and out transitions for the same slide: - -```html -
- The train goes on … -
-
- and on … -
-
- and stops. -
-
- (Passengers entering and leaving) -
-
- And it starts again. -
-``` -You can choose from `none`, `fade`, `slide`, `convex`, `concave` and `zoom`. -### Internal links - -It's easy to link between slides. The first example below targets the index of another slide whereas the second targets a slide with an ID attribute (`
`): - -```html -Link -Link -``` - -You can also add relative navigation links, similar to the built in reveal.js controls, by appending one of the following classes on any element. Note that each element is automatically given an `enabled` class when it's a valid navigation route based on the current slide. - -```html - - - - - - -``` - -### Fragments - -Fragments are used to highlight individual elements on a slide. Every element with the class `fragment` will be stepped through before moving on to the next slide. Here's an example: http://revealjs.com/#/fragments - -The default fragment style is to start out invisible and fade in. This style can be changed by appending a different class to the fragment: - -```html -
-

grow

-

shrink

-

strike

-

fade-out

-

fade-up (also down, left and right!)

-

fades in, then out when we move to the next step

-

fades in, then obfuscate when we move to the next step

-

blue only once

-

highlight-red

-

highlight-green

-

highlight-blue

-
-``` - -Multiple fragments can be applied to the same element sequentially by wrapping it, this will fade in the text on the first step and fade it back out on the second. - -```html -
- - I'll fade in, then out - -
-``` - -The display order of fragments can be controlled using the `data-fragment-index` attribute. - -```html -
-

Appears last

-

Appears first

-

Appears second

-
-``` - -### Fragment events - -When a slide fragment is either shown or hidden reveal.js will dispatch an event. - -Some libraries, like MathJax (see #505), get confused by the initially hidden fragment elements. Often times this can be fixed by calling their update or render function from this callback. - -```javascript -Reveal.on( 'fragmentshown', event => { - // event.fragment = the fragment DOM element -} ); -Reveal.on( 'fragmenthidden', event => { - // event.fragment = the fragment DOM element -} ); -``` - -### Code Syntax Highlighting - -By default, Reveal is configured with [highlight.js](https://highlightjs.org/) for code syntax highlighting. To enable syntax highlighting, you'll have to load the highlight plugin ([plugin/highlight/highlight.js](plugin/highlight/highlight.js)) and a highlight.js CSS theme (Reveal comes packaged with the Monokai themes: [lib/css/monokai.css](lib/css/monokai.css)). - -```javascript -Reveal.initialize({ - // More info https://github.com/hakimel/reveal.js#dependencies - dependencies: [ - { src: 'plugin/highlight/highlight.js', async: true }, - ] -}); -``` - -Below is an example with clojure code that will be syntax highlighted. When the `data-trim` attribute is present, surrounding whitespace is automatically removed. HTML will be escaped by default. To avoid this, for example if you are using `` to call out a line of code, add the `data-noescape` attribute to the `` element. - -```html -
- 

-(def lazy-fib
-  (concat
-   [0 1]
-   ((fn rfib [a b]
-        (lazy-cons (+ a b) (rfib b (+ a b)))) 0 1)))
-
-
-``` - -#### Line Numbers & Highlights - -To enable line numbers, add `data-line-numbers` to your `` tags. If you want to highlight specific lines you can provide a comma separated list of line numbers using the same attribute. For example, in the following example lines 4 and 8-11 are highlighted: - -```html -

-import React, { useState } from 'react';
- 
-function Example() {
-  const [count, setCount] = useState(0);
- 
-  return (
-    

-      
You clicked {count} times

-      
-    

-  );
-}
-
-``` - -line-numbers - -#### Step-by-step Highlights - -You can step through multiple code highlights on the same code block. Delimit each of your highlight steps with the `|` character. For example `data-line-numbers="1|2-3|4,6-10"` will produce three steps. It will start by highlighting line 1, next step is lines 2-3, and finally line 4 and 6 through 10. - - - -### Slide number - -If you would like to display the page number of the current slide you can do so using the `slideNumber` and `showSlideNumber` configuration values. - -```javascript -// Shows the slide number using default formatting -Reveal.configure({ slideNumber: true }); - -// Slide number formatting can be configured using these variables: -// "h.v": horizontal . vertical slide number (default) -// "h/v": horizontal / vertical slide number -// "c": flattened slide number -// "c/t": flattened slide number / total slides -Reveal.configure({ slideNumber: 'c/t' }); - -// You can provide a function to fully customize the number: -Reveal.configure({ slideNumber: slide => { - // Ignore numbering of vertical slides - return [ Reveal.getIndices( slide ).h ]; -}}); - -// Control which views the slide number displays on using the "showSlideNumber" value: -// "all": show on all views (default) -// "speaker": only show slide numbers on speaker notes view -// "print": only show slide numbers when printing to PDF -Reveal.configure({ showSlideNumber: 'speaker' }); -``` - -### Overview mode - -Press »ESC« or »O« keys to toggle the overview mode on and off. While you're in this mode, you can still navigate between slides, -as if you were at 1,000 feet above your presentation. The overview mode comes with a few API hooks: - -```javascript -Reveal.on( 'overviewshown', event => { /* ... */ } ); -Reveal.on( 'overviewhidden', event => { /* ... */ } ); - -// Toggle the overview mode programmatically -Reveal.toggleOverview(); -``` - -### Fullscreen mode - -Just press »F« on your keyboard to show your presentation in fullscreen mode. Press the »ESC« key to exit fullscreen mode. - -### Embedded media - -Add `data-autoplay` to your media element if you want it to automatically start playing when the slide is shown: - -```html - -``` - -If you want to enable or disable autoplay globally, for all embedded media, you can use the `autoPlayMedia` configuration option. If you set this to `true` ALL media will autoplay regardless of individual `data-autoplay` attributes. If you initialize with `autoPlayMedia: false` NO media will autoplay. - -Note that embedded HTML5 `