tubestats-presentation/js/reveal.js

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JavaScript
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This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

import SlideContent from './controllers/slidecontent.js'
import SlideNumber from './controllers/slidenumber.js'
import AutoAnimate from './controllers/autoanimate.js'
import Fragments from './controllers/fragments.js'
import Overview from './controllers/overview.js'
import Keyboard from './controllers/keyboard.js'
import Location from './controllers/location.js'
import Plugins from './controllers/plugins.js'
import Touch from './controllers/touch.js'
import Playback from './components/playback.js'
import defaultConfig from './config.js'
import { isMobile, isChrome, isAndroid, supportsZoom } from './utils/device.js'
import { colorToRgb, colorBrightness } from './utils/color.js'
import {
SLIDES_SELECTOR,
HORIZONTAL_SLIDES_SELECTOR,
VERTICAL_SLIDES_SELECTOR,
POST_MESSAGE_METHOD_BLACKLIST
} from './utils/constants.js'
import {
extend,
toArray,
distanceBetween,
deserialize,
transformElement,
createSingletonNode,
createStyleSheet,
closestParent,
enterFullscreen,
getQueryHash
} from './utils/util.js'
/**
* reveal.js
* http://revealjs.com
* MIT licensed
*
* Copyright (C) 2020 Hakim El Hattab, https://hakim.se
*/
export default function( revealElement, options ) {
const Reveal = {};
// The reveal.js version
const VERSION = '4.0.0-dev';
// Configuration defaults, can be overridden at initialization time
let config,
// Flags if reveal.js is loaded (has dispatched the 'ready' event)
ready = false,
// The horizontal and vertical index of the currently active slide
indexh,
indexv,
// The previous and current slide HTML elements
previousSlide,
currentSlide,
previousBackground,
// Remember which directions that the user has navigated towards
hasNavigatedHorizontally = false,
hasNavigatedVertically = false,
// Slides may hold a data-state attribute which we pick up and apply
// as a class to the body. This list contains the combined state of
// all current slides.
state = [],
// The current scale of the presentation (see width/height config)
scale = 1,
// Controls loading and playback of slide content
slideContent = new SlideContent( Reveal ),
// Controls the optional slide number display
slideNumber = new SlideNumber( Reveal ),
// Controls auto-animations between slides
autoAnimate = new AutoAnimate( Reveal ),
// Controls navigation between slide fragments
fragments = new Fragments( Reveal ),
// Controls the birds-eye overview of slides
overview = new Overview( Reveal ),
// Controls all keyboard interactions
keyboard = new Keyboard( Reveal ),
// Controls the current location/URL
location = new Location( Reveal ),
// Controller for plugin loading
plugins = new Plugins(),
// Controls touch/swipe navigation for our deck
touch = new Touch( Reveal ),
// CSS transform that is currently applied to the slides container,
// split into two groups
slidesTransform = { layout: '', overview: '' },
// Cached references to DOM elements
dom = {},
// List of asynchronously loaded reveal.js dependencies
asyncDependencies = [],
// Throttles mouse wheel navigation
lastMouseWheelStep = 0,
// Is the mouse pointer currently hidden from view
cursorHidden = false,
// Timeout used to determine when the cursor is inactive
cursorInactiveTimeout = 0,
// Flags if the interaction event listeners are bound
eventsAreBound = false,
// The current auto-slide duration
autoSlide = 0,
// Auto slide properties
autoSlidePlayer,
autoSlideTimeout = 0,
autoSlideStartTime = -1,
autoSlidePaused = false;
/**
* Starts up the presentation if the client is capable.
*/
function initialize() {
if( !revealElement ) {
console.warn( 'reveal.js can not initialize without a valid .reveal element.' );
return;
}
// Cache references to key DOM elements
dom.wrapper = revealElement;
dom.slides = revealElement.querySelector( '.slides' );
// Force a layout when the whole page, incl fonts, has loaded
window.addEventListener( 'load', layout, false );
// Copy options over to our config object
config = { ...defaultConfig, ...options, ...getQueryHash() };
// Load plugins then move on to #start()
plugins.load( config.dependencies ).then( start )
return new Promise( resolve => Reveal.addEventListener( 'ready', resolve ) );
}
/**
* Starts up reveal.js by binding input events and navigating
* to the current URL deeplink if there is one.
*/
function start() {
ready = true;
// Make sure we've got all the DOM elements we need
setupDOM();
// Listen to messages posted to this window
setupPostMessage();
// Prevent the slides from being scrolled out of view
setupScrollPrevention();
// Resets all vertical slides so that only the first is visible
resetVerticalSlides();
// Updates the presentation to match the current configuration values
configure();
// Read the initial hash
location.readURL();
// Update all backgrounds
updateBackground( true );
// Notify listeners that the presentation is ready but use a 1ms
// timeout to ensure it's not fired synchronously after #initialize()
setTimeout( () => {
// Enable transitions now that we're loaded
dom.slides.classList.remove( 'no-transition' );
dom.wrapper.classList.add( 'ready' );
dispatchEvent({
type: 'ready',
data: {
indexh,
indexv,
currentSlide
}
});
}, 1 );
// Special setup and config is required when printing to PDF
if( isPrintingPDF() ) {
removeEventListeners();
// The document needs to have loaded for the PDF layout
// measurements to be accurate
if( document.readyState === 'complete' ) {
setupPDF();
}
else {
window.addEventListener( 'load', setupPDF );
}
}
}
/**
* Finds and stores references to DOM elements which are
* required by the presentation. If a required element is
* not found, it is created.
*/
function setupDOM() {
// Prevent transitions while we're loading
dom.slides.classList.add( 'no-transition' );
if( isMobile ) {
dom.wrapper.classList.add( 'no-hover' );
}
else {
dom.wrapper.classList.remove( 'no-hover' );
}
// Background element
dom.background = createSingletonNode( dom.wrapper, 'div', 'backgrounds', null );
// Progress bar
dom.progress = createSingletonNode( dom.wrapper, 'div', 'progress', '<span></span>' );
dom.progressbar = dom.progress.querySelector( 'span' );
// Arrow controls
dom.controls = createSingletonNode( dom.wrapper, 'aside', 'controls',
`<button class="navigate-left" aria-label="${ config.rtl ? 'next slide' : 'previous slide' }"><div class="controls-arrow"></div></button>
<button class="navigate-right" aria-label="${ config.rtl ? 'previous slide' : 'next slide' }"><div class="controls-arrow"></div></button>
<button class="navigate-up" aria-label="above slide"><div class="controls-arrow"></div></button>
<button class="navigate-down" aria-label="below slide"><div class="controls-arrow"></div></button>` );
// Slide number
slideNumber.createElement();
// Element containing notes that are visible to the audience
dom.speakerNotes = createSingletonNode( dom.wrapper, 'div', 'speaker-notes', null );
dom.speakerNotes.setAttribute( 'data-prevent-swipe', '' );
dom.speakerNotes.setAttribute( 'tabindex', '0' );
// Overlay graphic which is displayed during the paused mode
dom.pauseOverlay = createSingletonNode( dom.wrapper, 'div', 'pause-overlay', config.controls ? '<button class="resume-button">Resume presentation</button>' : null );
dom.wrapper.setAttribute( 'role', 'application' );
// There can be multiple instances of controls throughout the page
dom.controlsLeft = toArray( dom.wrapper.querySelectorAll( '.navigate-left' ) );
dom.controlsRight = toArray( dom.wrapper.querySelectorAll( '.navigate-right' ) );
dom.controlsUp = toArray( dom.wrapper.querySelectorAll( '.navigate-up' ) );
dom.controlsDown = toArray( dom.wrapper.querySelectorAll( '.navigate-down' ) );
dom.controlsPrev = toArray( dom.wrapper.querySelectorAll( '.navigate-prev' ) );
dom.controlsNext = toArray( dom.wrapper.querySelectorAll( '.navigate-next' ) );
// The left, right and down arrows in the standard reveal.js controls
dom.controlsRightArrow = dom.controls.querySelector( '.navigate-right' );
dom.controlsLeftArrow = dom.controls.querySelector( '.navigate-left' );
dom.controlsDownArrow = dom.controls.querySelector( '.navigate-down' );
dom.statusElement = createStatusElement();
}
/**
* Creates a hidden div with role aria-live to announce the
* current slide content. Hide the div off-screen to make it
* available only to Assistive Technologies.
*
* @return {HTMLElement}
*/
function createStatusElement() {
let statusElement = dom.wrapper.querySelector( '.aria-status' );
if( !statusElement ) {
statusElement = document.createElement( 'div' );
statusElement.style.position = 'absolute';
statusElement.style.height = '1px';
statusElement.style.width = '1px';
statusElement.style.overflow = 'hidden';
statusElement.style.clip = 'rect( 1px, 1px, 1px, 1px )';
statusElement.classList.add( 'aria-status' );
statusElement.setAttribute( 'aria-live', 'polite' );
statusElement.setAttribute( 'aria-atomic','true' );
dom.wrapper.appendChild( statusElement );
}
return statusElement;
}
/**
* Announces the given text to screen readers.
*/
function announceStatus( value ) {
dom.statusElement.textContent = value;
}
/**
* Converts the given HTML element into a string of text
* that can be announced to a screen reader. Hidden
* elements are excluded.
*/
function getStatusText( node ) {
let text = '';
// Text node
if( node.nodeType === 3 ) {
text += node.textContent;
}
// Element node
else if( node.nodeType === 1 ) {
let isAriaHidden = node.getAttribute( 'aria-hidden' );
let isDisplayHidden = window.getComputedStyle( node )['display'] === 'none';
if( isAriaHidden !== 'true' && !isDisplayHidden ) {
toArray( node.childNodes ).forEach( child => {
text += getStatusText( child );
} );
}
}
text = text.trim();
return text === '' ? '' : text + ' ';
}
/**
* Configures the presentation for printing to a static
* PDF.
*/
function setupPDF() {
let slideSize = getComputedSlideSize( window.innerWidth, window.innerHeight );
// Dimensions of the PDF pages
let pageWidth = Math.floor( slideSize.width * ( 1 + config.margin ) ),
pageHeight = Math.floor( slideSize.height * ( 1 + config.margin ) );
// Dimensions of slides within the pages
let slideWidth = slideSize.width,
slideHeight = slideSize.height;
// Let the browser know what page size we want to print
createStyleSheet( '@page{size:'+ pageWidth +'px '+ pageHeight +'px; margin: 0px;}' );
// Limit the size of certain elements to the dimensions of the slide
createStyleSheet( '.reveal section>img, .reveal section>video, .reveal section>iframe{max-width: '+ slideWidth +'px; max-height:'+ slideHeight +'px}' );
document.body.classList.add( 'print-pdf' );
document.body.style.width = pageWidth + 'px';
document.body.style.height = pageHeight + 'px';
// Make sure stretch elements fit on slide
layoutSlideContents( slideWidth, slideHeight );
// Compute slide numbers now, before we start duplicating slides
let doingSlideNumbers = config.slideNumber && /all|print/i.test( config.showSlideNumber );
toArray( dom.wrapper.querySelectorAll( SLIDES_SELECTOR ) ).forEach( function( slide ) {
slide.setAttribute( 'data-slide-number', slideNumber.getSlideNumber( slide ) );
} );
// Slide and slide background layout
toArray( dom.wrapper.querySelectorAll( SLIDES_SELECTOR ) ).forEach( function( slide ) {
// Vertical stacks are not centred since their section
// children will be
if( slide.classList.contains( 'stack' ) === false ) {
// Center the slide inside of the page, giving the slide some margin
let left = ( pageWidth - slideWidth ) / 2,
top = ( pageHeight - slideHeight ) / 2;
let contentHeight = slide.scrollHeight;
let numberOfPages = Math.max( Math.ceil( contentHeight / pageHeight ), 1 );
// Adhere to configured pages per slide limit
numberOfPages = Math.min( numberOfPages, config.pdfMaxPagesPerSlide );
// Center slides vertically
if( numberOfPages === 1 && config.center || slide.classList.contains( 'center' ) ) {
top = Math.max( ( pageHeight - contentHeight ) / 2, 0 );
}
// Wrap the slide in a page element and hide its overflow
// so that no page ever flows onto another
let page = document.createElement( 'div' );
page.className = 'pdf-page';
page.style.height = ( ( pageHeight + config.pdfPageHeightOffset ) * numberOfPages ) + 'px';
slide.parentNode.insertBefore( page, slide );
page.appendChild( slide );
// Position the slide inside of the page
slide.style.left = left + 'px';
slide.style.top = top + 'px';
slide.style.width = slideWidth + 'px';
if( slide.slideBackgroundElement ) {
page.insertBefore( slide.slideBackgroundElement, slide );
}
// Inject notes if `showNotes` is enabled
if( config.showNotes ) {
// Are there notes for this slide?
let notes = getSlideNotes( slide );
if( notes ) {
let notesSpacing = 8;
let notesLayout = typeof config.showNotes === 'string' ? config.showNotes : 'inline';
let notesElement = document.createElement( 'div' );
notesElement.classList.add( 'speaker-notes' );
notesElement.classList.add( 'speaker-notes-pdf' );
notesElement.setAttribute( 'data-layout', notesLayout );
notesElement.innerHTML = notes;
if( notesLayout === 'separate-page' ) {
page.parentNode.insertBefore( notesElement, page.nextSibling );
}
else {
notesElement.style.left = notesSpacing + 'px';
notesElement.style.bottom = notesSpacing + 'px';
notesElement.style.width = ( pageWidth - notesSpacing*2 ) + 'px';
page.appendChild( notesElement );
}
}
}
// Inject slide numbers if `slideNumbers` are enabled
if( doingSlideNumbers ) {
let numberElement = document.createElement( 'div' );
numberElement.classList.add( 'slide-number' );
numberElement.classList.add( 'slide-number-pdf' );
numberElement.innerHTML = slide.getAttribute( 'data-slide-number' );
page.appendChild( numberElement );
}
// Copy page and show fragments one after another
if( config.pdfSeparateFragments ) {
// Each fragment 'group' is an array containing one or more
// fragments. Multiple fragments that appear at the same time
// are part of the same group.
let fragmentGroups = fragments.sort( page.querySelectorAll( '.fragment' ), true );
let previousFragmentStep;
let previousPage;
fragmentGroups.forEach( function( fragments ) {
// Remove 'current-fragment' from the previous group
if( previousFragmentStep ) {
previousFragmentStep.forEach( function( fragment ) {
fragment.classList.remove( 'current-fragment' );
} );
}
// Show the fragments for the current index
fragments.forEach( function( fragment ) {
fragment.classList.add( 'visible', 'current-fragment' );
} );
// Create a separate page for the current fragment state
let clonedPage = page.cloneNode( true );
page.parentNode.insertBefore( clonedPage, ( previousPage || page ).nextSibling );
previousFragmentStep = fragments;
previousPage = clonedPage;
} );
// Reset the first/original page so that all fragments are hidden
fragmentGroups.forEach( function( fragments ) {
fragments.forEach( function( fragment ) {
fragment.classList.remove( 'visible', 'current-fragment' );
} );
} );
}
// Show all fragments
else {
toArray( page.querySelectorAll( '.fragment:not(.fade-out)' ) ).forEach( function( fragment ) {
fragment.classList.add( 'visible' );
} );
}
}
} );
// Notify subscribers that the PDF layout is good to go
dispatchEvent({ type: 'pdf-ready' });
}
/**
* This is an unfortunate necessity. Some actions such as
* an input field being focused in an iframe or using the
* keyboard to expand text selection beyond the bounds of
* a slide can trigger our content to be pushed out of view.
* This scrolling can not be prevented by hiding overflow in
* CSS (we already do) so we have to resort to repeatedly
* checking if the slides have been offset :(
*/
function setupScrollPrevention() {
setInterval( () => {
if( dom.wrapper.scrollTop !== 0 || dom.wrapper.scrollLeft !== 0 ) {
dom.wrapper.scrollTop = 0;
dom.wrapper.scrollLeft = 0;
}
}, 1000 );
}
/**
* Creates the slide background elements and appends them
* to the background container. One element is created per
* slide no matter if the given slide has visible background.
*/
function createBackgrounds() {
let printMode = isPrintingPDF();
// Clear prior backgrounds
dom.background.innerHTML = '';
dom.background.classList.add( 'no-transition' );
// Iterate over all horizontal slides
toArray( dom.wrapper.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR ) ).forEach( slideh => {
let backgroundStack = createBackground( slideh, dom.background );
// Iterate over all vertical slides
toArray( slideh.querySelectorAll( 'section' ) ).forEach( slidev => {
createBackground( slidev, backgroundStack );
backgroundStack.classList.add( 'stack' );
} );
} );
// Add parallax background if specified
if( config.parallaxBackgroundImage ) {
dom.background.style.backgroundImage = 'url("' + config.parallaxBackgroundImage + '")';
dom.background.style.backgroundSize = config.parallaxBackgroundSize;
dom.background.style.backgroundRepeat = config.parallaxBackgroundRepeat;
dom.background.style.backgroundPosition = config.parallaxBackgroundPosition;
// Make sure the below properties are set on the element - these properties are
// needed for proper transitions to be set on the element via CSS. To remove
// annoying background slide-in effect when the presentation starts, apply
// these properties after short time delay
setTimeout( () => {
dom.wrapper.classList.add( 'has-parallax-background' );
}, 1 );
}
else {
dom.background.style.backgroundImage = '';
dom.wrapper.classList.remove( 'has-parallax-background' );
}
}
/**
* Creates a background for the given slide.
*
* @param {HTMLElement} slide
* @param {HTMLElement} container The element that the background
* should be appended to
* @return {HTMLElement} New background div
*/
function createBackground( slide, container ) {
// Main slide background element
let element = document.createElement( 'div' );
element.className = 'slide-background ' + slide.className.replace( /present|past|future/, '' );
// Inner background element that wraps images/videos/iframes
let contentElement = document.createElement( 'div' );
contentElement.className = 'slide-background-content';
element.appendChild( contentElement );
container.appendChild( element );
slide.slideBackgroundElement = element;
slide.slideBackgroundContentElement = contentElement;
// Syncs the background to reflect all current background settings
syncBackground( slide );
return element;
}
/**
* Renders all of the visual properties of a slide background
* based on the various background attributes.
*
* @param {HTMLElement} slide
*/
function syncBackground( slide ) {
let element = slide.slideBackgroundElement,
contentElement = slide.slideBackgroundContentElement;
// Reset the prior background state in case this is not the
// initial sync
slide.classList.remove( 'has-dark-background' );
slide.classList.remove( 'has-light-background' );
element.removeAttribute( 'data-loaded' );
element.removeAttribute( 'data-background-hash' );
element.removeAttribute( 'data-background-size' );
element.removeAttribute( 'data-background-transition' );
element.style.backgroundColor = '';
contentElement.style.backgroundSize = '';
contentElement.style.backgroundRepeat = '';
contentElement.style.backgroundPosition = '';
contentElement.style.backgroundImage = '';
contentElement.style.opacity = '';
contentElement.innerHTML = '';
let data = {
background: slide.getAttribute( 'data-background' ),
backgroundSize: slide.getAttribute( 'data-background-size' ),
backgroundImage: slide.getAttribute( 'data-background-image' ),
backgroundVideo: slide.getAttribute( 'data-background-video' ),
backgroundIframe: slide.getAttribute( 'data-background-iframe' ),
backgroundColor: slide.getAttribute( 'data-background-color' ),
backgroundRepeat: slide.getAttribute( 'data-background-repeat' ),
backgroundPosition: slide.getAttribute( 'data-background-position' ),
backgroundTransition: slide.getAttribute( 'data-background-transition' ),
backgroundOpacity: slide.getAttribute( 'data-background-opacity' )
};
if( data.background ) {
// Auto-wrap image urls in url(...)
if( /^(http|file|\/\/)/gi.test( data.background ) || /\.(svg|png|jpg|jpeg|gif|bmp)([?#\s]|$)/gi.test( data.background ) ) {
slide.setAttribute( 'data-background-image', data.background );
}
else {
element.style.background = data.background;
}
}
// Create a hash for this combination of background settings.
// This is used to determine when two slide backgrounds are
// the same.
if( data.background || data.backgroundColor || data.backgroundImage || data.backgroundVideo || data.backgroundIframe ) {
element.setAttribute( 'data-background-hash', data.background +
data.backgroundSize +
data.backgroundImage +
data.backgroundVideo +
data.backgroundIframe +
data.backgroundColor +
data.backgroundRepeat +
data.backgroundPosition +
data.backgroundTransition +
data.backgroundOpacity );
}
// Additional and optional background properties
if( data.backgroundSize ) element.setAttribute( 'data-background-size', data.backgroundSize );
if( data.backgroundColor ) element.style.backgroundColor = data.backgroundColor;
if( data.backgroundTransition ) element.setAttribute( 'data-background-transition', data.backgroundTransition );
if( slide.hasAttribute( 'data-preload' ) ) element.setAttribute( 'data-preload', '' );
// Background image options are set on the content wrapper
if( data.backgroundSize ) contentElement.style.backgroundSize = data.backgroundSize;
if( data.backgroundRepeat ) contentElement.style.backgroundRepeat = data.backgroundRepeat;
if( data.backgroundPosition ) contentElement.style.backgroundPosition = data.backgroundPosition;
if( data.backgroundOpacity ) contentElement.style.opacity = data.backgroundOpacity;
// If this slide has a background color, we add a class that
// signals if it is light or dark. If the slide has no background
// color, no class will be added
let contrastColor = data.backgroundColor;
// If no bg color was found, check the computed background
if( !contrastColor ) {
let computedBackgroundStyle = window.getComputedStyle( element );
if( computedBackgroundStyle && computedBackgroundStyle.backgroundColor ) {
contrastColor = computedBackgroundStyle.backgroundColor;
}
}
if( contrastColor ) {
let rgb = colorToRgb( contrastColor );
// Ignore fully transparent backgrounds. Some browsers return
// rgba(0,0,0,0) when reading the computed background color of
// an element with no background
if( rgb && rgb.a !== 0 ) {
if( colorBrightness( contrastColor ) < 128 ) {
slide.classList.add( 'has-dark-background' );
}
else {
slide.classList.add( 'has-light-background' );
}
}
}
}
/**
* Registers a listener to postMessage events, this makes it
* possible to call all reveal.js API methods from another
* window. For example:
*
* revealWindow.postMessage( JSON.stringify({
* method: 'slide',
* args: [ 2 ]
* }), '*' );
*/
function setupPostMessage() {
if( config.postMessage ) {
window.addEventListener( 'message', event => {
let data = event.data;
// Make sure we're dealing with JSON
if( typeof data === 'string' && data.charAt( 0 ) === '{' && data.charAt( data.length - 1 ) === '}' ) {
data = JSON.parse( data );
// Check if the requested method can be found
if( data.method && typeof Reveal[data.method] === 'function' ) {
if( POST_MESSAGE_METHOD_BLACKLIST.test( data.method ) === false ) {
const result = Reveal[data.method].apply( Reveal, data.args );
// Dispatch a postMessage event with the returned value from
// our method invocation for getter functions
dispatchPostMessage( 'callback', { method: data.method, result: result } );
}
else {
console.warn( 'reveal.js: "'+ data.method +'" is is blacklisted from the postMessage API' );
}
}
}
}, false );
}
}
/**
* Applies the configuration settings from the config
* object. May be called multiple times.
*
* @param {object} options
*/
function configure( options ) {
const oldConfig = { ...config }
// New config options may be passed when this method
// is invoked through the API after initialization
if( typeof options === 'object' ) extend( config, options );
// Abort if reveal.js hasn't finished loading, config
// changes will be applied automatically once ready
if( Reveal.isReady() === false ) return;
const numberOfSlides = dom.wrapper.querySelectorAll( SLIDES_SELECTOR ).length;
// The transition is added as a class on the .reveal element
dom.wrapper.classList.remove( oldConfig.transition );
dom.wrapper.classList.add( config.transition );
dom.wrapper.setAttribute( 'data-transition-speed', config.transitionSpeed );
dom.wrapper.setAttribute( 'data-background-transition', config.backgroundTransition );
dom.controls.style.display = config.controls ? 'block' : 'none';
dom.progress.style.display = config.progress ? 'block' : 'none';
dom.controls.setAttribute( 'data-controls-layout', config.controlsLayout );
dom.controls.setAttribute( 'data-controls-back-arrows', config.controlsBackArrows );
if( config.shuffle ) {
shuffle();
}
if( config.rtl ) {
dom.wrapper.classList.add( 'rtl' );
}
else {
dom.wrapper.classList.remove( 'rtl' );
}
if( config.center ) {
dom.wrapper.classList.add( 'center' );
}
else {
dom.wrapper.classList.remove( 'center' );
}
// Exit the paused mode if it was configured off
if( config.pause === false ) {
resume();
}
if( config.showNotes ) {
dom.speakerNotes.setAttribute( 'data-layout', typeof config.showNotes === 'string' ? config.showNotes : 'inline' );
}
if( config.mouseWheel ) {
document.addEventListener( 'DOMMouseScroll', onDocumentMouseScroll, false ); // FF
document.addEventListener( 'mousewheel', onDocumentMouseScroll, false );
}
else {
document.removeEventListener( 'DOMMouseScroll', onDocumentMouseScroll, false ); // FF
document.removeEventListener( 'mousewheel', onDocumentMouseScroll, false );
}
// Auto-hide the mouse pointer when its inactive
if( config.hideInactiveCursor ) {
document.addEventListener( 'mousemove', onDocumentCursorActive, false );
document.addEventListener( 'mousedown', onDocumentCursorActive, false );
}
else {
showCursor();
document.removeEventListener( 'mousemove', onDocumentCursorActive, false );
document.removeEventListener( 'mousedown', onDocumentCursorActive, false );
}
// Iframe link previews
if( config.previewLinks ) {
enablePreviewLinks();
disablePreviewLinks( '[data-preview-link=false]' );
}
else {
disablePreviewLinks();
enablePreviewLinks( '[data-preview-link]:not([data-preview-link=false])' );
}
// Reset all changes made by auto-animations
autoAnimate.reset();
// Remove existing auto-slide controls
if( autoSlidePlayer ) {
autoSlidePlayer.destroy();
autoSlidePlayer = null;
}
// Generate auto-slide controls if needed
if( numberOfSlides > 1 && config.autoSlide && config.autoSlideStoppable ) {
autoSlidePlayer = new Playback( dom.wrapper, () => {
return Math.min( Math.max( ( Date.now() - autoSlideStartTime ) / autoSlide, 0 ), 1 );
} );
autoSlidePlayer.on( 'click', onAutoSlidePlayerClick );
autoSlidePaused = false;
}
// Update the state of our fragments
if( config.fragments === false ) {
fragments.disable();
}
else if( oldConfig.fragments === false ) {
fragments.enable();
}
// Add the navigation mode to the DOM so we can adjust styling
if( config.navigationMode !== 'default' ) {
dom.wrapper.setAttribute( 'data-navigation-mode', config.navigationMode );
}
else {
dom.wrapper.removeAttribute( 'data-navigation-mode' );
}
slideNumber.refreshVisibility();
keyboard.refreshSortcuts();
sync();
}
/**
* Binds all event listeners.
*/
function addEventListeners() {
eventsAreBound = true;
window.addEventListener( 'hashchange', onWindowHashChange, false );
window.addEventListener( 'resize', onWindowResize, false );
if( config.touch ) {
touch.bind();
}
if( config.keyboard ) {
keyboard.bind();
}
if( config.progress && dom.progress ) {
dom.progress.addEventListener( 'click', onProgressClicked, false );
}
dom.pauseOverlay.addEventListener( 'click', resume, false );
if( config.focusBodyOnPageVisibilityChange ) {
document.addEventListener( 'visibilitychange', onPageVisibilityChange, false );
}
// Listen to both touch and click events, in case the device
// supports both
let pointerEvents = [ 'touchstart', 'click' ];
// Only support touch for Android, fixes double navigations in
// stock browser
if( isAndroid ) {
pointerEvents = [ 'touchstart' ];
}
pointerEvents.forEach( eventName => {
dom.controlsLeft.forEach( el => el.addEventListener( eventName, onNavigateLeftClicked, false ) );
dom.controlsRight.forEach( el => el.addEventListener( eventName, onNavigateRightClicked, false ) );
dom.controlsUp.forEach( el => el.addEventListener( eventName, onNavigateUpClicked, false ) );
dom.controlsDown.forEach( el => el.addEventListener( eventName, onNavigateDownClicked, false ) );
dom.controlsPrev.forEach( el => el.addEventListener( eventName, onNavigatePrevClicked, false ) );
dom.controlsNext.forEach( el => el.addEventListener( eventName, onNavigateNextClicked, false ) );
} );
}
/**
* Unbinds all event listeners.
*/
function removeEventListeners() {
eventsAreBound = false;
touch.unbind();
keyboard.unbind();
window.removeEventListener( 'hashchange', onWindowHashChange, false );
window.removeEventListener( 'resize', onWindowResize, false );
dom.pauseOverlay.removeEventListener( 'click', resume, false );
if ( config.progress && dom.progress ) {
dom.progress.removeEventListener( 'click', onProgressClicked, false );
}
[ 'touchstart', 'click' ].forEach( eventName => {
dom.controlsLeft.forEach( el => el.removeEventListener( eventName, onNavigateLeftClicked, false ) );
dom.controlsRight.forEach( el => el.removeEventListener( eventName, onNavigateRightClicked, false ) );
dom.controlsUp.forEach( el => el.removeEventListener( eventName, onNavigateUpClicked, false ) );
dom.controlsDown.forEach( el => el.removeEventListener( eventName, onNavigateDownClicked, false ) );
dom.controlsPrev.forEach( el => el.removeEventListener( eventName, onNavigatePrevClicked, false ) );
dom.controlsNext.forEach( el => el.removeEventListener( eventName, onNavigateNextClicked, false ) );
} );
}
/**
* Applies CSS transforms to the slides container. The container
* is transformed from two separate sources: layout and the overview
* mode.
*
* @param {object} transforms
*/
function transformSlides( transforms ) {
// Pick up new transforms from arguments
if( typeof transforms.layout === 'string' ) slidesTransform.layout = transforms.layout;
if( typeof transforms.overview === 'string' ) slidesTransform.overview = transforms.overview;
// Apply the transforms to the slides container
if( slidesTransform.layout ) {
transformElement( dom.slides, slidesTransform.layout + ' ' + slidesTransform.overview );
}
else {
transformElement( dom.slides, slidesTransform.overview );
}
}
/**
* Returns the remaining height within the parent of the
* target element.
*
* remaining height = [ configured parent height ] - [ current parent height ]
*
* @param {HTMLElement} element
* @param {number} [height]
*/
function getRemainingHeight( element, height = 0 ) {
if( element ) {
let newHeight, oldHeight = element.style.height;
// Change the .stretch element height to 0 in order find the height of all
// the other elements
element.style.height = '0px';
// In Overview mode, the parent (.slide) height is set of 700px.
// Restore it temporarily to its natural height.
element.parentNode.style.height = 'auto';
newHeight = height - element.parentNode.offsetHeight;
// Restore the old height, just in case
element.style.height = oldHeight + 'px';
// Clear the parent (.slide) height. .removeProperty works in IE9+
element.parentNode.style.removeProperty('height');
return newHeight;
}
return height;
}
/**
* Checks if this instance is being used to print a PDF.
*/
function isPrintingPDF() {
return ( /print-pdf/gi ).test( window.location.search );
}
/**
* Dispatches an event of the specified type from the
* reveal DOM element.
*/
function dispatchEvent({ target=dom.wrapper, type, data, bubbles=true }) {
let event = document.createEvent( 'HTMLEvents', 1, 2 );
event.initEvent( type, bubbles, true );
extend( event, data );
target.dispatchEvent( event );
if( target === dom.wrapper ) {
// If we're in an iframe, post each reveal.js event to the
// parent window. Used by the notes plugin
dispatchPostMessage( type );
}
}
/**
* Dispatched a postMessage of the given type from our window.
*/
function dispatchPostMessage( type, data ) {
if( config.postMessageEvents && window.parent !== window.self ) {
let message = {
namespace: 'reveal',
eventName: type,
state: getState()
};
extend( message, data );
window.parent.postMessage( JSON.stringify( message ), '*' );
}
}
/**
* Bind preview frame links.
*
* @param {string} [selector=a] - selector for anchors
*/
function enablePreviewLinks( selector = 'a' ) {
toArray( dom.wrapper.querySelectorAll( selector ) ).forEach( element => {
if( /^(http|www)/gi.test( element.getAttribute( 'href' ) ) ) {
element.addEventListener( 'click', onPreviewLinkClicked, false );
}
} );
}
/**
* Unbind preview frame links.
*/
function disablePreviewLinks( selector = 'a' ) {
toArray( dom.wrapper.querySelectorAll( selector ) ).forEach( element => {
if( /^(http|www)/gi.test( element.getAttribute( 'href' ) ) ) {
element.removeEventListener( 'click', onPreviewLinkClicked, false );
}
} );
}
/**
* Opens a preview window for the target URL.
*
* @param {string} url - url for preview iframe src
*/
function showPreview( url ) {
closeOverlay();
dom.overlay = document.createElement( 'div' );
dom.overlay.classList.add( 'overlay' );
dom.overlay.classList.add( 'overlay-preview' );
dom.wrapper.appendChild( dom.overlay );
dom.overlay.innerHTML =
`<header>
<a class="close" href="#"><span class="icon"></span></a>
<a class="external" href="${url}" target="_blank"><span class="icon"></span></a>
</header>
<div class="spinner"></div>
<div class="viewport">
<iframe src="${url}"></iframe>
<small class="viewport-inner">
<span class="x-frame-error">Unable to load iframe. This is likely due to the site's policy (x-frame-options).</span>
</small>
</div>`;
dom.overlay.querySelector( 'iframe' ).addEventListener( 'load', event => {
dom.overlay.classList.add( 'loaded' );
}, false );
dom.overlay.querySelector( '.close' ).addEventListener( 'click', event => {
closeOverlay();
event.preventDefault();
}, false );
dom.overlay.querySelector( '.external' ).addEventListener( 'click', event => {
closeOverlay();
}, false );
}
/**
* Open or close help overlay window.
*
* @param {Boolean} [override] Flag which overrides the
* toggle logic and forcibly sets the desired state. True means
* help is open, false means it's closed.
*/
function toggleHelp( override ){
if( typeof override === 'boolean' ) {
override ? showHelp() : closeOverlay();
}
else {
if( dom.overlay ) {
closeOverlay();
}
else {
showHelp();
}
}
}
/**
* Opens an overlay window with help material.
*/
function showHelp() {
if( config.help ) {
closeOverlay();
dom.overlay = document.createElement( 'div' );
dom.overlay.classList.add( 'overlay' );
dom.overlay.classList.add( 'overlay-help' );
dom.wrapper.appendChild( dom.overlay );
let html = '<p class="title">Keyboard Shortcuts</p><br/>';
html += '<table><th>KEY</th><th>ACTION</th>';
for( let key in keyboard.shortcuts ) {
html += `<tr><td>${key}</td><td>${keyboard.shortcuts[ key ]}</td></tr>`;
}
// Add custom key bindings that have associated descriptions
for( let binding in keyboard.registeredKeyBindings ) {
if( keyboard.registeredKeyBindings[binding].key && keyboard.registeredKeyBindings[binding].description ) {
html += `<tr><td>${keyboard.registeredKeyBindings[binding].key}</td><td>${keyboard.registeredKeyBindings[binding].description}</td></tr>`;
}
}
html += '</table>';
dom.overlay.innerHTML = `
<header>
<a class="close" href="#"><span class="icon"></span></a>
</header>
<div class="viewport">
<div class="viewport-inner">${html}</div>
</div>
`;
dom.overlay.querySelector( '.close' ).addEventListener( 'click', event => {
closeOverlay();
event.preventDefault();
}, false );
}
}
/**
* Closes any currently open overlay.
*/
function closeOverlay() {
if( dom.overlay ) {
dom.overlay.parentNode.removeChild( dom.overlay );
dom.overlay = null;
return true;
}
return false;
}
/**
* Applies JavaScript-controlled layout rules to the
* presentation.
*/
function layout() {
if( dom.wrapper && !isPrintingPDF() ) {
if( !config.disableLayout ) {
// On some mobile devices '100vh' is taller than the visible
// viewport which leads to part of the presentation being
// cut off. To work around this we define our own '--vh' custom
// property where 100x adds up to the correct height.
//
// https://css-tricks.com/the-trick-to-viewport-units-on-mobile/
if( isMobile ) {
document.documentElement.style.setProperty( '--vh', ( window.innerHeight * 0.01 ) + 'px' );
}
const size = getComputedSlideSize();
const oldScale = scale;
// Layout the contents of the slides
layoutSlideContents( config.width, config.height );
dom.slides.style.width = size.width + 'px';
dom.slides.style.height = size.height + 'px';
// Determine scale of content to fit within available space
scale = Math.min( size.presentationWidth / size.width, size.presentationHeight / size.height );
// Respect max/min scale settings
scale = Math.max( scale, config.minScale );
scale = Math.min( scale, config.maxScale );
// Don't apply any scaling styles if scale is 1
if( scale === 1 ) {
dom.slides.style.zoom = '';
dom.slides.style.left = '';
dom.slides.style.top = '';
dom.slides.style.bottom = '';
dom.slides.style.right = '';
transformSlides( { layout: '' } );
}
else {
// Zoom Scaling
// Content remains crisp no matter how much we scale. Side
// effects are minor differences in text layout and iframe
// viewports changing size. A 200x200 iframe viewport in a
// 2x zoomed presentation ends up having a 400x400 viewport.
if( scale > 1 && supportsZoom && window.devicePixelRatio < 2 ) {
dom.slides.style.zoom = scale;
dom.slides.style.left = '';
dom.slides.style.top = '';
dom.slides.style.bottom = '';
dom.slides.style.right = '';
transformSlides( { layout: '' } );
}
// Transform Scaling
// Content layout remains the exact same when scaled up.
// Side effect is content becoming blurred, especially with
// high scale values on ldpi screens.
else {
dom.slides.style.zoom = '';
dom.slides.style.left = '50%';
dom.slides.style.top = '50%';
dom.slides.style.bottom = 'auto';
dom.slides.style.right = 'auto';
transformSlides( { layout: 'translate(-50%, -50%) scale('+ scale +')' } );
}
}
// Select all slides, vertical and horizontal
const slides = toArray( dom.wrapper.querySelectorAll( SLIDES_SELECTOR ) );
for( let i = 0, len = slides.length; i < len; i++ ) {
const slide = slides[ i ];
// Don't bother updating invisible slides
if( slide.style.display === 'none' ) {
continue;
}
if( config.center || slide.classList.contains( 'center' ) ) {
// Vertical stacks are not centred since their section
// children will be
if( slide.classList.contains( 'stack' ) ) {
slide.style.top = 0;
}
else {
slide.style.top = Math.max( ( size.height - slide.scrollHeight ) / 2, 0 ) + 'px';
}
}
else {
slide.style.top = '';
}
}
if( oldScale !== scale ) {
dispatchEvent({
type: 'resize',
data: {
oldScale,
scale,
size
}
});
}
}
updateProgress();
updateParallax();
if( overview.isActive() ) {
overview.update();
}
}
}
/**
* Applies layout logic to the contents of all slides in
* the presentation.
*
* @param {string|number} width
* @param {string|number} height
*/
function layoutSlideContents( width, height ) {
// Handle sizing of elements with the 'stretch' class
toArray( dom.slides.querySelectorAll( 'section > .stretch' ) ).forEach( element => {
// Determine how much vertical space we can use
let remainingHeight = getRemainingHeight( element, height );
// Consider the aspect ratio of media elements
if( /(img|video)/gi.test( element.nodeName ) ) {
const nw = element.naturalWidth || element.videoWidth,
nh = element.naturalHeight || element.videoHeight;
const es = Math.min( width / nw, remainingHeight / nh );
element.style.width = ( nw * es ) + 'px';
element.style.height = ( nh * es ) + 'px';
}
else {
element.style.width = width + 'px';
element.style.height = remainingHeight + 'px';
}
} );
}
/**
* Calculates the computed pixel size of our slides. These
* values are based on the width and height configuration
* options.
*
* @param {number} [presentationWidth=dom.wrapper.offsetWidth]
* @param {number} [presentationHeight=dom.wrapper.offsetHeight]
*/
function getComputedSlideSize( presentationWidth, presentationHeight ) {
const size = {
// Slide size
width: config.width,
height: config.height,
// Presentation size
presentationWidth: presentationWidth || dom.wrapper.offsetWidth,
presentationHeight: presentationHeight || dom.wrapper.offsetHeight
};
// Reduce available space by margin
size.presentationWidth -= ( size.presentationWidth * config.margin );
size.presentationHeight -= ( size.presentationHeight * config.margin );
// Slide width may be a percentage of available width
if( typeof size.width === 'string' && /%$/.test( size.width ) ) {
size.width = parseInt( size.width, 10 ) / 100 * size.presentationWidth;
}
// Slide height may be a percentage of available height
if( typeof size.height === 'string' && /%$/.test( size.height ) ) {
size.height = parseInt( size.height, 10 ) / 100 * size.presentationHeight;
}
return size;
}
/**
* Stores the vertical index of a stack so that the same
* vertical slide can be selected when navigating to and
* from the stack.
*
* @param {HTMLElement} stack The vertical stack element
* @param {string|number} [v=0] Index to memorize
*/
function setPreviousVerticalIndex( stack, v ) {
if( typeof stack === 'object' && typeof stack.setAttribute === 'function' ) {
stack.setAttribute( 'data-previous-indexv', v || 0 );
}
}
/**
* Retrieves the vertical index which was stored using
* #setPreviousVerticalIndex() or 0 if no previous index
* exists.
*
* @param {HTMLElement} stack The vertical stack element
*/
function getPreviousVerticalIndex( stack ) {
if( typeof stack === 'object' && typeof stack.setAttribute === 'function' && stack.classList.contains( 'stack' ) ) {
// Prefer manually defined start-indexv
const attributeName = stack.hasAttribute( 'data-start-indexv' ) ? 'data-start-indexv' : 'data-previous-indexv';
return parseInt( stack.getAttribute( attributeName ) || 0, 10 );
}
return 0;
}
/**
* Checks if the current or specified slide is vertical
* (nested within another slide).
*
* @param {HTMLElement} [slide=currentSlide] The slide to check
* orientation of
* @return {Boolean}
*/
function isVerticalSlide( slide = currentSlide ) {
return slide && slide.parentNode && !!slide.parentNode.nodeName.match( /section/i );
}
/**
* Returns true if we're on the last slide in the current
* vertical stack.
*/
function isLastVerticalSlide() {
if( currentSlide && isVerticalSlide( currentSlide ) ) {
// Does this slide have a next sibling?
if( currentSlide.nextElementSibling ) return false;
return true;
}
return false;
}
/**
* Returns true if we're currently on the first slide in
* the presentation.
*/
function isFirstSlide() {
return indexh === 0 && indexv === 0;
}
/**
* Returns true if we're currently on the last slide in
* the presenation. If the last slide is a stack, we only
* consider this the last slide if it's at the end of the
* stack.
*/
function isLastSlide() {
if( currentSlide ) {
// Does this slide have a next sibling?
if( currentSlide.nextElementSibling ) return false;
// If it's vertical, does its parent have a next sibling?
if( isVerticalSlide( currentSlide ) && currentSlide.parentNode.nextElementSibling ) return false;
return true;
}
return false;
}
/**
* Shows the mouse pointer after it has been hidden with
* #hideCursor.
*/
function showCursor() {
if( cursorHidden ) {
cursorHidden = false;
dom.wrapper.style.cursor = '';
}
}
/**
* Hides the mouse pointer when it's on top of the .reveal
* container.
*/
function hideCursor() {
if( cursorHidden === false ) {
cursorHidden = true;
dom.wrapper.style.cursor = 'none';
}
}
/**
* Enters the paused mode which fades everything on screen to
* black.
*/
function pause() {
if( config.pause ) {
const wasPaused = dom.wrapper.classList.contains( 'paused' );
cancelAutoSlide();
dom.wrapper.classList.add( 'paused' );
if( wasPaused === false ) {
dispatchEvent({ type: 'paused' });
}
}
}
/**
* Exits from the paused mode.
*/
function resume() {
const wasPaused = dom.wrapper.classList.contains( 'paused' );
dom.wrapper.classList.remove( 'paused' );
cueAutoSlide();
if( wasPaused ) {
dispatchEvent({ type: 'resumed' });
}
}
/**
* Toggles the paused mode on and off.
*/
function togglePause( override ) {
if( typeof override === 'boolean' ) {
override ? pause() : resume();
}
else {
isPaused() ? resume() : pause();
}
}
/**
* Checks if we are currently in the paused mode.
*
* @return {Boolean}
*/
function isPaused() {
return dom.wrapper.classList.contains( 'paused' );
}
/**
* Toggles the auto slide mode on and off.
*
* @param {Boolean} [override] Flag which sets the desired state.
* True means autoplay starts, false means it stops.
*/
function toggleAutoSlide( override ) {
if( typeof override === 'boolean' ) {
override ? resumeAutoSlide() : pauseAutoSlide();
}
else {
autoSlidePaused ? resumeAutoSlide() : pauseAutoSlide();
}
}
/**
* Checks if the auto slide mode is currently on.
*
* @return {Boolean}
*/
function isAutoSliding() {
return !!( autoSlide && !autoSlidePaused );
}
/**
* Steps from the current point in the presentation to the
* slide which matches the specified horizontal and vertical
* indices.
*
* @param {number} [h=indexh] Horizontal index of the target slide
* @param {number} [v=indexv] Vertical index of the target slide
* @param {number} [f] Index of a fragment within the
* target slide to activate
* @param {number} [o] Origin for use in multimaster environments
*/
function slide( h, v, f, o ) {
// Remember where we were at before
previousSlide = currentSlide;
// Query all horizontal slides in the deck
const horizontalSlides = dom.wrapper.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR );
// Abort if there are no slides
if( horizontalSlides.length === 0 ) return;
// If no vertical index is specified and the upcoming slide is a
// stack, resume at its previous vertical index
if( v === undefined && !overview.isActive() ) {
v = getPreviousVerticalIndex( horizontalSlides[ h ] );
}
// If we were on a vertical stack, remember what vertical index
// it was on so we can resume at the same position when returning
if( previousSlide && previousSlide.parentNode && previousSlide.parentNode.classList.contains( 'stack' ) ) {
setPreviousVerticalIndex( previousSlide.parentNode, indexv );
}
// Remember the state before this slide
const stateBefore = state.concat();
// Reset the state array
state.length = 0;
let indexhBefore = indexh || 0,
indexvBefore = indexv || 0;
// Activate and transition to the new slide
indexh = updateSlides( HORIZONTAL_SLIDES_SELECTOR, h === undefined ? indexh : h );
indexv = updateSlides( VERTICAL_SLIDES_SELECTOR, v === undefined ? indexv : v );
// Update the visibility of slides now that the indices have changed
updateSlidesVisibility();
layout();
// Update the overview if it's currently active
if( overview.isActive() ) {
overview.update();
}
// Find the current horizontal slide and any possible vertical slides
// within it
let currentHorizontalSlide = horizontalSlides[ indexh ],
currentVerticalSlides = currentHorizontalSlide.querySelectorAll( 'section' );
// Store references to the previous and current slides
currentSlide = currentVerticalSlides[ indexv ] || currentHorizontalSlide;
// Show fragment, if specified
if( typeof f !== 'undefined' ) {
fragments.goto( f );
}
// Dispatch an event if the slide changed
let slideChanged = ( indexh !== indexhBefore || indexv !== indexvBefore );
if (!slideChanged) {
// Ensure that the previous slide is never the same as the current
previousSlide = null;
}
// Solves an edge case where the previous slide maintains the
// 'present' class when navigating between adjacent vertical
// stacks
if( previousSlide && previousSlide !== currentSlide ) {
previousSlide.classList.remove( 'present' );
previousSlide.setAttribute( 'aria-hidden', 'true' );
// Reset all slides upon navigate to home
if( isFirstSlide() ) {
// Launch async task
setTimeout( () => {
getVerticalStacks().forEach( slide => {
setPreviousVerticalIndex( slide, 0 );
} );
}, 0 );
}
}
// Apply the new state
stateLoop: for( let i = 0, len = state.length; i < len; i++ ) {
// Check if this state existed on the previous slide. If it
// did, we will avoid adding it repeatedly
for( let j = 0; j < stateBefore.length; j++ ) {
if( stateBefore[j] === state[i] ) {
stateBefore.splice( j, 1 );
continue stateLoop;
}
}
document.documentElement.classList.add( state[i] );
// Dispatch custom event matching the state's name
dispatchEvent({ type: state[i] });
}
// Clean up the remains of the previous state
while( stateBefore.length ) {
document.documentElement.classList.remove( stateBefore.pop() );
}
if( slideChanged ) {
dispatchEvent({
type: 'slidechanged',
data: {
indexh,
indexv,
previousSlide,
currentSlide,
origin: o
}
});
}
// Handle embedded content
if( slideChanged || !previousSlide ) {
slideContent.stopEmbeddedContent( previousSlide );
slideContent.startEmbeddedContent( currentSlide );
}
// Announce the current slide contents to screen readers
announceStatus( getStatusText( currentSlide ) );
updateControls();
updateProgress();
updateBackground();
updateParallax();
updateNotes();
slideNumber.update();
fragments.update();
// Update the URL hash
location.writeURL();
cueAutoSlide();
// Auto-animation
if( slideChanged && previousSlide && currentSlide && !overview.isActive() ) {
// Skip the slide transition between our two slides
// when auto-animating individual elements
if( previousSlide.hasAttribute( 'data-auto-animate' ) && currentSlide.hasAttribute( 'data-auto-animate' ) ) {
dom.slides.classList.add( 'disable-slide-transitions' );
setTimeout( () => {
dom.slides.classList.remove( 'disable-slide-transitions' );
}, 0 );
if( config.autoAnimate ) {
// Run the auto-animation between our slides
autoAnimate.run( previousSlide, currentSlide );
}
}
}
}
/**
* Syncs the presentation with the current DOM. Useful
* when new slides or control elements are added or when
* the configuration has changed.
*/
function sync() {
// Subscribe to input
removeEventListeners();
addEventListeners();
// Force a layout to make sure the current config is accounted for
layout();
// Reflect the current autoSlide value
autoSlide = config.autoSlide;
// Start auto-sliding if it's enabled
cueAutoSlide();
// Re-create the slide backgrounds
createBackgrounds();
// Write the current hash to the URL
location.writeURL();
fragments.sortAll();
updateControls();
updateProgress();
updateSlidesVisibility();
updateBackground( true );
updateNotesVisibility();
updateNotes();
slideNumber.update();
slideContent.formatEmbeddedContent();
// Start or stop embedded content depending on global config
if( config.autoPlayMedia === false ) {
slideContent.stopEmbeddedContent( currentSlide, { unloadIframes: false } );
}
else {
slideContent.startEmbeddedContent( currentSlide );
}
if( overview.isActive() ) {
overview.layout();
}
}
/**
* Updates reveal.js to keep in sync with new slide attributes. For
* example, if you add a new `data-background-image` you can call
* this to have reveal.js render the new background image.
*
* Similar to #sync() but more efficient when you only need to
* refresh a specific slide.
*
* @param {HTMLElement} slide
*/
function syncSlide( slide = currentSlide ) {
syncBackground( slide );
syncFragments( slide );
slideContent.load( slide );
updateBackground();
updateNotes();
}
/**
* Formats the fragments on the given slide so that they have
* valid indices. Call this if fragments are changed in the DOM
* after reveal.js has already initialized.
*
* @param {HTMLElement} slide
* @return {Array} a list of the HTML fragments that were synced
*/
function syncFragments( slide = currentSlide ) {
return config.sort( slide.querySelectorAll( '.fragment' ) );
}
/**
* Resets all vertical slides so that only the first
* is visible.
*/
function resetVerticalSlides() {
getHorizontalSlides().forEach( horizontalSlide => {
toArray( horizontalSlide.querySelectorAll( 'section' ) ).forEach( ( verticalSlide, y ) => {
if( y > 0 ) {
verticalSlide.classList.remove( 'present' );
verticalSlide.classList.remove( 'past' );
verticalSlide.classList.add( 'future' );
verticalSlide.setAttribute( 'aria-hidden', 'true' );
}
} );
} );
}
/**
* Randomly shuffles all slides in the deck.
*/
function shuffle() {
getHorizontalSlides().forEach( ( slide, i, slides ) => {
// Insert this slide next to another random slide. This may
// cause the slide to insert before itself but that's fine.
dom.slides.insertBefore( slide, slides[ Math.floor( Math.random() * slides.length ) ] );
} );
}
/**
* Updates one dimension of slides by showing the slide
* with the specified index.
*
* @param {string} selector A CSS selector that will fetch
* the group of slides we are working with
* @param {number} index The index of the slide that should be
* shown
*
* @return {number} The index of the slide that is now shown,
* might differ from the passed in index if it was out of
* bounds.
*/
function updateSlides( selector, index ) {
// Select all slides and convert the NodeList result to
// an array
let slides = toArray( dom.wrapper.querySelectorAll( selector ) ),
slidesLength = slides.length;
let printMode = isPrintingPDF();
if( slidesLength ) {
// Should the index loop?
if( config.loop ) {
index %= slidesLength;
if( index < 0 ) {
index = slidesLength + index;
}
}
// Enforce max and minimum index bounds
index = Math.max( Math.min( index, slidesLength - 1 ), 0 );
for( let i = 0; i < slidesLength; i++ ) {
let element = slides[i];
let reverse = config.rtl && !isVerticalSlide( element );
element.classList.remove( 'past', 'present', 'future' );
// http://www.w3.org/html/wg/drafts/html/master/editing.html#the-hidden-attribute
element.setAttribute( 'hidden', '' );
element.setAttribute( 'aria-hidden', 'true' );
// If this element contains vertical slides
if( element.querySelector( 'section' ) ) {
element.classList.add( 'stack' );
}
// If we're printing static slides, all slides are "present"
if( printMode ) {
element.classList.add( 'present' );
continue;
}
if( i < index ) {
// Any element previous to index is given the 'past' class
element.classList.add( reverse ? 'future' : 'past' );
if( config.fragments ) {
// Show all fragments in prior slides
toArray( element.querySelectorAll( '.fragment' ) ).forEach( fragment => {
fragment.classList.add( 'visible' );
fragment.classList.remove( 'current-fragment' );
} );
}
}
else if( i > index ) {
// Any element subsequent to index is given the 'future' class
element.classList.add( reverse ? 'past' : 'future' );
if( config.fragments ) {
// Hide all fragments in future slides
toArray( element.querySelectorAll( '.fragment.visible' ) ).forEach( fragment => {
fragment.classList.remove( 'visible', 'current-fragment' );
} );
}
}
}
let slide = slides[index];
let wasPresent = slide.classList.contains( 'present' );
// Mark the current slide as present
slide.classList.add( 'present' );
slide.removeAttribute( 'hidden' );
slide.removeAttribute( 'aria-hidden' );
if( !wasPresent ) {
// Dispatch an event indicating the slide is now visible
dispatchEvent({
target: slide,
type: 'visible',
bubbles: false
});
}
// If this slide has a state associated with it, add it
// onto the current state of the deck
let slideState = slide.getAttribute( 'data-state' );
if( slideState ) {
state = state.concat( slideState.split( ' ' ) );
}
}
else {
// Since there are no slides we can't be anywhere beyond the
// zeroth index
index = 0;
}
return index;
}
/**
* Optimization method; hide all slides that are far away
* from the present slide.
*/
function updateSlidesVisibility() {
// Select all slides and convert the NodeList result to
// an array
let horizontalSlides = getHorizontalSlides(),
horizontalSlidesLength = horizontalSlides.length,
distanceX,
distanceY;
if( horizontalSlidesLength && typeof indexh !== 'undefined' ) {
// The number of steps away from the present slide that will
// be visible
let viewDistance = overview.isActive() ? 10 : config.viewDistance;
// Shorten the view distance on devices that typically have
// less resources
if( isMobile ) {
viewDistance = overview.isActive() ? 6 : config.mobileViewDistance;
}
// All slides need to be visible when exporting to PDF
if( isPrintingPDF() ) {
viewDistance = Number.MAX_VALUE;
}
for( let x = 0; x < horizontalSlidesLength; x++ ) {
let horizontalSlide = horizontalSlides[x];
let verticalSlides = toArray( horizontalSlide.querySelectorAll( 'section' ) ),
verticalSlidesLength = verticalSlides.length;
// Determine how far away this slide is from the present
distanceX = Math.abs( ( indexh || 0 ) - x ) || 0;
// If the presentation is looped, distance should measure
// 1 between the first and last slides
if( config.loop ) {
distanceX = Math.abs( ( ( indexh || 0 ) - x ) % ( horizontalSlidesLength - viewDistance ) ) || 0;
}
// Show the horizontal slide if it's within the view distance
if( distanceX < viewDistance ) {
slideContent.load( horizontalSlide );
}
else {
slideContent.unload( horizontalSlide );
}
if( verticalSlidesLength ) {
let oy = getPreviousVerticalIndex( horizontalSlide );
for( let y = 0; y < verticalSlidesLength; y++ ) {
let verticalSlide = verticalSlides[y];
distanceY = x === ( indexh || 0 ) ? Math.abs( ( indexv || 0 ) - y ) : Math.abs( y - oy );
if( distanceX + distanceY < viewDistance ) {
slideContent.load( verticalSlide );
}
else {
slideContent.unload( verticalSlide );
}
}
}
}
// Flag if there are ANY vertical slides, anywhere in the deck
if( hasVerticalSlides() ) {
dom.wrapper.classList.add( 'has-vertical-slides' );
}
else {
dom.wrapper.classList.remove( 'has-vertical-slides' );
}
// Flag if there are ANY horizontal slides, anywhere in the deck
if( hasHorizontalSlides() ) {
dom.wrapper.classList.add( 'has-horizontal-slides' );
}
else {
dom.wrapper.classList.remove( 'has-horizontal-slides' );
}
}
}
/**
* Pick up notes from the current slide and display them
* to the viewer.
*
* @see {@link config.showNotes}
*/
function updateNotes() {
if( config.showNotes && dom.speakerNotes && currentSlide && !isPrintingPDF() ) {
dom.speakerNotes.innerHTML = getSlideNotes() || '<span class="notes-placeholder">No notes on this slide.</span>';
}
}
/**
* Updates the visibility of the speaker notes sidebar that
* is used to share annotated slides. The notes sidebar is
* only visible if showNotes is true and there are notes on
* one or more slides in the deck.
*/
function updateNotesVisibility() {
if( config.showNotes && hasNotes() ) {
dom.wrapper.classList.add( 'show-notes' );
}
else {
dom.wrapper.classList.remove( 'show-notes' );
}
}
/**
* Checks if there are speaker notes for ANY slide in the
* presentation.
*/
function hasNotes() {
return dom.slides.querySelectorAll( '[data-notes], aside.notes' ).length > 0;
}
/**
* Updates the progress bar to reflect the current slide.
*/
function updateProgress() {
// Update progress if enabled
if( config.progress && dom.progressbar ) {
dom.progressbar.style.width = getProgress() * dom.wrapper.offsetWidth + 'px';
}
}
/**
* Updates the state of all control/navigation arrows.
*/
function updateControls() {
let routes = availableRoutes();
let fragmentsRoutes = fragments.availableRoutes();
// Remove the 'enabled' class from all directions
[...dom.controlsLeft, ...dom.controlsRight, ...dom.controlsUp, ...dom.controlsDown, ...dom.controlsPrev, ...dom.controlsNext].forEach( node => {
node.classList.remove( 'enabled', 'fragmented' );
// Set 'disabled' attribute on all directions
node.setAttribute( 'disabled', 'disabled' );
} );
// Add the 'enabled' class to the available routes; remove 'disabled' attribute to enable buttons
if( routes.left ) dom.controlsLeft.forEach( el => { el.classList.add( 'enabled' ); el.removeAttribute( 'disabled' ); } );
if( routes.right ) dom.controlsRight.forEach( el => { el.classList.add( 'enabled' ); el.removeAttribute( 'disabled' ); } );
if( routes.up ) dom.controlsUp.forEach( el => { el.classList.add( 'enabled' ); el.removeAttribute( 'disabled' ); } );
if( routes.down ) dom.controlsDown.forEach( el => { el.classList.add( 'enabled' ); el.removeAttribute( 'disabled' ); } );
// Prev/next buttons
if( routes.left || routes.up ) dom.controlsPrev.forEach( el => { el.classList.add( 'enabled' ); el.removeAttribute( 'disabled' ); } );
if( routes.right || routes.down ) dom.controlsNext.forEach( el => { el.classList.add( 'enabled' ); el.removeAttribute( 'disabled' ); } );
// Highlight fragment directions
if( currentSlide ) {
// Always apply fragment decorator to prev/next buttons
if( fragmentsRoutes.prev ) dom.controlsPrev.forEach( el => { el.classList.add( 'fragmented', 'enabled' ); el.removeAttribute( 'disabled' ); } );
if( fragmentsRoutes.next ) dom.controlsNext.forEach( el => { el.classList.add( 'fragmented', 'enabled' ); el.removeAttribute( 'disabled' ); } );
// Apply fragment decorators to directional buttons based on
// what slide axis they are in
if( isVerticalSlide( currentSlide ) ) {
if( fragmentsRoutes.prev ) dom.controlsUp.forEach( el => { el.classList.add( 'fragmented', 'enabled' ); el.removeAttribute( 'disabled' ); } );
if( fragmentsRoutes.next ) dom.controlsDown.forEach( el => { el.classList.add( 'fragmented', 'enabled' ); el.removeAttribute( 'disabled' ); } );
}
else {
if( fragmentsRoutes.prev ) dom.controlsLeft.forEach( el => { el.classList.add( 'fragmented', 'enabled' ); el.removeAttribute( 'disabled' ); } );
if( fragmentsRoutes.next ) dom.controlsRight.forEach( el => { el.classList.add( 'fragmented', 'enabled' ); el.removeAttribute( 'disabled' ); } );
}
}
if( config.controlsTutorial ) {
// Highlight control arrows with an animation to ensure
// that the viewer knows how to navigate
if( !hasNavigatedVertically && routes.down ) {
dom.controlsDownArrow.classList.add( 'highlight' );
}
else {
dom.controlsDownArrow.classList.remove( 'highlight' );
if( config.rtl ) {
if( !hasNavigatedHorizontally && routes.left && indexv === 0 ) {
dom.controlsLeftArrow.classList.add( 'highlight' );
}
else {
dom.controlsLeftArrow.classList.remove( 'highlight' );
}
} else {
if( !hasNavigatedHorizontally && routes.right && indexv === 0 ) {
dom.controlsRightArrow.classList.add( 'highlight' );
}
else {
dom.controlsRightArrow.classList.remove( 'highlight' );
}
}
}
}
}
/**
* Updates the background elements to reflect the current
* slide.
*
* @param {boolean} includeAll If true, the backgrounds of
* all vertical slides (not just the present) will be updated.
*/
function updateBackground( includeAll = false ) {
let currentBackground = null;
// Reverse past/future classes when in RTL mode
let horizontalPast = config.rtl ? 'future' : 'past',
horizontalFuture = config.rtl ? 'past' : 'future';
// Update the classes of all backgrounds to match the
// states of their slides (past/present/future)
toArray( dom.background.childNodes ).forEach( ( backgroundh, h ) => {
backgroundh.classList.remove( 'past', 'present', 'future' );
if( h < indexh ) {
backgroundh.classList.add( horizontalPast );
}
else if ( h > indexh ) {
backgroundh.classList.add( horizontalFuture );
}
else {
backgroundh.classList.add( 'present' );
// Store a reference to the current background element
currentBackground = backgroundh;
}
if( includeAll || h === indexh ) {
toArray( backgroundh.querySelectorAll( '.slide-background' ) ).forEach( ( backgroundv, v ) => {
backgroundv.classList.remove( 'past', 'present', 'future' );
if( v < indexv ) {
backgroundv.classList.add( 'past' );
}
else if ( v > indexv ) {
backgroundv.classList.add( 'future' );
}
else {
backgroundv.classList.add( 'present' );
// Only if this is the present horizontal and vertical slide
if( h === indexh ) currentBackground = backgroundv;
}
} );
}
} );
// Stop content inside of previous backgrounds
if( previousBackground ) {
slideContent.stopEmbeddedContent( previousBackground, { unloadIframes: !slideContent.shouldPreload( previousBackground ) } );
}
// Start content in the current background
if( currentBackground ) {
slideContent.startEmbeddedContent( currentBackground );
let currentBackgroundContent = currentBackground.querySelector( '.slide-background-content' );
if( currentBackgroundContent ) {
let backgroundImageURL = currentBackgroundContent.style.backgroundImage || '';
// Restart GIFs (doesn't work in Firefox)
if( /\.gif/i.test( backgroundImageURL ) ) {
currentBackgroundContent.style.backgroundImage = '';
window.getComputedStyle( currentBackgroundContent ).opacity;
currentBackgroundContent.style.backgroundImage = backgroundImageURL;
}
}
// Don't transition between identical backgrounds. This
// prevents unwanted flicker.
let previousBackgroundHash = previousBackground ? previousBackground.getAttribute( 'data-background-hash' ) : null;
let currentBackgroundHash = currentBackground.getAttribute( 'data-background-hash' );
if( currentBackgroundHash && currentBackgroundHash === previousBackgroundHash && currentBackground !== previousBackground ) {
dom.background.classList.add( 'no-transition' );
}
previousBackground = currentBackground;
}
// If there's a background brightness flag for this slide,
// bubble it to the .reveal container
if( currentSlide ) {
[ 'has-light-background', 'has-dark-background' ].forEach( classToBubble => {
if( currentSlide.classList.contains( classToBubble ) ) {
dom.wrapper.classList.add( classToBubble );
}
else {
dom.wrapper.classList.remove( classToBubble );
}
} );
}
// Allow the first background to apply without transition
setTimeout( () => {
dom.background.classList.remove( 'no-transition' );
}, 1 );
}
/**
* Updates the position of the parallax background based
* on the current slide index.
*/
function updateParallax() {
if( config.parallaxBackgroundImage ) {
let horizontalSlides = getHorizontalSlides(),
verticalSlides = getVerticalSlides();
let backgroundSize = dom.background.style.backgroundSize.split( ' ' ),
backgroundWidth, backgroundHeight;
if( backgroundSize.length === 1 ) {
backgroundWidth = backgroundHeight = parseInt( backgroundSize[0], 10 );
}
else {
backgroundWidth = parseInt( backgroundSize[0], 10 );
backgroundHeight = parseInt( backgroundSize[1], 10 );
}
let slideWidth = dom.background.offsetWidth,
horizontalSlideCount = horizontalSlides.length,
horizontalOffsetMultiplier,
horizontalOffset;
if( typeof config.parallaxBackgroundHorizontal === 'number' ) {
horizontalOffsetMultiplier = config.parallaxBackgroundHorizontal;
}
else {
horizontalOffsetMultiplier = horizontalSlideCount > 1 ? ( backgroundWidth - slideWidth ) / ( horizontalSlideCount-1 ) : 0;
}
horizontalOffset = horizontalOffsetMultiplier * indexh * -1;
let slideHeight = dom.background.offsetHeight,
verticalSlideCount = verticalSlides.length,
verticalOffsetMultiplier,
verticalOffset;
if( typeof config.parallaxBackgroundVertical === 'number' ) {
verticalOffsetMultiplier = config.parallaxBackgroundVertical;
}
else {
verticalOffsetMultiplier = ( backgroundHeight - slideHeight ) / ( verticalSlideCount-1 );
}
verticalOffset = verticalSlideCount > 0 ? verticalOffsetMultiplier * indexv : 0;
dom.background.style.backgroundPosition = horizontalOffset + 'px ' + -verticalOffset + 'px';
}
}
/**
* Determine what available routes there are for navigation.
*
* @return {{left: boolean, right: boolean, up: boolean, down: boolean}}
*/
function availableRoutes() {
let horizontalSlides = dom.wrapper.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR ),
verticalSlides = dom.wrapper.querySelectorAll( VERTICAL_SLIDES_SELECTOR );
let routes = {
left: indexh > 0,
right: indexh < horizontalSlides.length - 1,
up: indexv > 0,
down: indexv < verticalSlides.length - 1
};
// Looped presentations can always be navigated as long as
// there are slides available
if( config.loop ) {
if( horizontalSlides.length > 1 ) {
routes.left = true;
routes.right = true;
}
if( verticalSlides.length > 1 ) {
routes.up = true;
routes.down = true;
}
}
if ( horizontalSlides.length > 1 && config.navigationMode === 'linear' ) {
routes.right = routes.right || routes.down;
routes.left = routes.left || routes.up;
}
// Reverse horizontal controls for rtl
if( config.rtl ) {
let left = routes.left;
routes.left = routes.right;
routes.right = left;
}
return routes;
}
/**
* Returns the number of past slides. This can be used as a global
* flattened index for slides.
*
* @param {HTMLElement} [slide=currentSlide] The slide we're counting before
*
* @return {number} Past slide count
*/
function getSlidePastCount( slide = currentSlide ) {
let horizontalSlides = getHorizontalSlides();
// The number of past slides
let pastCount = 0;
// Step through all slides and count the past ones
mainLoop: for( let i = 0; i < horizontalSlides.length; i++ ) {
let horizontalSlide = horizontalSlides[i];
let verticalSlides = horizontalSlide.querySelectorAll( 'section' );
for( let j = 0; j < verticalSlides.length; j++ ) {
// Stop as soon as we arrive at the present
if( verticalSlides[j] === slide ) {
break mainLoop;
}
// Don't count slides with the "uncounted" class
if( verticalSlides[j].dataset.visibility !== 'uncounted' ) {
pastCount++;
}
}
// Stop as soon as we arrive at the present
if( horizontalSlide === slide ) {
break;
}
// Don't count the wrapping section for vertical slides and
// slides marked as uncounted
if( horizontalSlide.classList.contains( 'stack' ) === false && !horizontalSlide.dataset.visibility !== 'uncounted' ) {
pastCount++;
}
}
return pastCount;
}
/**
* Returns a value ranging from 0-1 that represents
* how far into the presentation we have navigated.
*
* @return {number}
*/
function getProgress() {
// The number of past and total slides
let totalCount = getTotalSlides();
let pastCount = getSlidePastCount();
if( currentSlide ) {
let allFragments = currentSlide.querySelectorAll( '.fragment' );
// If there are fragments in the current slide those should be
// accounted for in the progress.
if( allFragments.length > 0 ) {
let visibleFragments = currentSlide.querySelectorAll( '.fragment.visible' );
// This value represents how big a portion of the slide progress
// that is made up by its fragments (0-1)
let fragmentWeight = 0.9;
// Add fragment progress to the past slide count
pastCount += ( visibleFragments.length / allFragments.length ) * fragmentWeight;
}
}
return Math.min( pastCount / ( totalCount - 1 ), 1 );
}
/**
* Checks if this presentation is running inside of the
* speaker notes window.
*
* @return {boolean}
*/
function isSpeakerNotes() {
return !!window.location.search.match( /receiver/gi );
}
/**
* Retrieves the h/v location and fragment of the current,
* or specified, slide.
*
* @param {HTMLElement} [slide] If specified, the returned
* index will be for this slide rather than the currently
* active one
*
* @return {{h: number, v: number, f: number}}
*/
function getIndices( slide ) {
// By default, return the current indices
let h = indexh,
v = indexv,
f;
// If a slide is specified, return the indices of that slide
if( slide ) {
let isVertical = isVerticalSlide( slide );
let slideh = isVertical ? slide.parentNode : slide;
// Select all horizontal slides
let horizontalSlides = toArray( dom.wrapper.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR ) );
// Now that we know which the horizontal slide is, get its index
h = Math.max( horizontalSlides.indexOf( slideh ), 0 );
// Assume we're not vertical
v = undefined;
// If this is a vertical slide, grab the vertical index
if( isVertical ) {
v = Math.max( toArray( slide.parentNode.querySelectorAll( 'section' ) ).indexOf( slide ), 0 );
}
}
if( !slide && currentSlide ) {
let hasFragments = currentSlide.querySelectorAll( '.fragment' ).length > 0;
if( hasFragments ) {
let currentFragment = currentSlide.querySelector( '.current-fragment' );
if( currentFragment && currentFragment.hasAttribute( 'data-fragment-index' ) ) {
f = parseInt( currentFragment.getAttribute( 'data-fragment-index' ), 10 );
}
else {
f = currentSlide.querySelectorAll( '.fragment.visible' ).length - 1;
}
}
}
return { h, v, f };
}
/**
* Retrieves all slides in this presentation.
*/
function getSlides() {
return toArray( dom.wrapper.querySelectorAll( SLIDES_SELECTOR + ':not(.stack):not([data-visibility="uncounted"])' ) );
}
/**
* Returns a list of all horizontal slides in the deck. Each
* vertical stack is included as one horizontal slide in the
* resulting array.
*/
function getHorizontalSlides() {
return toArray( dom.wrapper.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR ) );
}
/**
* Returns all vertical slides that exist within this deck.
*/
function getVerticalSlides() {
return toArray( dom.wrapper.querySelectorAll( '.slides>section>section' ) );
}
/**
* Returns all vertical stacks (each stack can contain multiple slides).
*/
function getVerticalStacks() {
return toArray( dom.wrapper.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR + '.stack') );
}
/**
* Returns true if there are at least two horizontal slides.
*/
function hasHorizontalSlides() {
return getHorizontalSlides().length > 1;
}
/**
* Returns true if there are at least two vertical slides.
*/
function hasVerticalSlides() {
return getVerticalSlides().length > 1;
}
/**
* Returns an array of objects where each object represents the
* attributes on its respective slide.
*/
function getSlidesAttributes() {
return getSlides().map( slide => {
let attributes = {};
for( let i = 0; i < slide.attributes.length; i++ ) {
let attribute = slide.attributes[ i ];
attributes[ attribute.name ] = attribute.value;
}
return attributes;
} );
}
/**
* Retrieves the total number of slides in this presentation.
*
* @return {number}
*/
function getTotalSlides() {
return getSlides().length;
}
/**
* Returns the slide element matching the specified index.
*
* @return {HTMLElement}
*/
function getSlide( x, y ) {
let horizontalSlide = getHorizontalSlides()[ x ];
let verticalSlides = horizontalSlide && horizontalSlide.querySelectorAll( 'section' );
if( verticalSlides && verticalSlides.length && typeof y === 'number' ) {
return verticalSlides ? verticalSlides[ y ] : undefined;
}
return horizontalSlide;
}
/**
* Returns the background element for the given slide.
* All slides, even the ones with no background properties
* defined, have a background element so as long as the
* index is valid an element will be returned.
*
* @param {mixed} x Horizontal background index OR a slide
* HTML element
* @param {number} y Vertical background index
* @return {(HTMLElement[]|*)}
*/
function getSlideBackground( x, y ) {
let slide = typeof x === 'number' ? getSlide( x, y ) : x;
if( slide ) {
return slide.slideBackgroundElement;
}
return undefined;
}
/**
* Retrieves the speaker notes from a slide. Notes can be
* defined in two ways:
* 1. As a data-notes attribute on the slide <section>
* 2. As an <aside class="notes"> inside of the slide
*
* @param {HTMLElement} [slide=currentSlide]
* @return {(string|null)}
*/
function getSlideNotes( slide = currentSlide ) {
// Notes can be specified via the data-notes attribute...
if( slide.hasAttribute( 'data-notes' ) ) {
return slide.getAttribute( 'data-notes' );
}
// ... or using an <aside class="notes"> element
let notesElement = slide.querySelector( 'aside.notes' );
if( notesElement ) {
return notesElement.innerHTML;
}
return null;
}
/**
* Retrieves the current state of the presentation as
* an object. This state can then be restored at any
* time.
*
* @return {{indexh: number, indexv: number, indexf: number, paused: boolean, overview: boolean}}
*/
function getState() {
let indices = getIndices();
return {
indexh: indices.h,
indexv: indices.v,
indexf: indices.f,
paused: isPaused(),
overview: overview.isActive()
};
}
/**
* Restores the presentation to the given state.
*
* @param {object} state As generated by getState()
* @see {@link getState} generates the parameter `state`
*/
function setState( state ) {
if( typeof state === 'object' ) {
slide( deserialize( state.indexh ), deserialize( state.indexv ), deserialize( state.indexf ) );
let pausedFlag = deserialize( state.paused ),
overviewFlag = deserialize( state.overview );
if( typeof pausedFlag === 'boolean' && pausedFlag !== isPaused() ) {
togglePause( pausedFlag );
}
if( typeof overviewFlag === 'boolean' && overviewFlag !== overview.isActive() ) {
overview.toggle( overviewFlag );
}
}
}
/**
* Cues a new automated slide if enabled in the config.
*/
function cueAutoSlide() {
cancelAutoSlide();
if( currentSlide && config.autoSlide !== false ) {
let fragment = currentSlide.querySelector( '.current-fragment' );
// When the slide first appears there is no "current" fragment so
// we look for a data-autoslide timing on the first fragment
if( !fragment ) fragment = currentSlide.querySelector( '.fragment' );
let fragmentAutoSlide = fragment ? fragment.getAttribute( 'data-autoslide' ) : null;
let parentAutoSlide = currentSlide.parentNode ? currentSlide.parentNode.getAttribute( 'data-autoslide' ) : null;
let slideAutoSlide = currentSlide.getAttribute( 'data-autoslide' );
// Pick value in the following priority order:
// 1. Current fragment's data-autoslide
// 2. Current slide's data-autoslide
// 3. Parent slide's data-autoslide
// 4. Global autoSlide setting
if( fragmentAutoSlide ) {
autoSlide = parseInt( fragmentAutoSlide, 10 );
}
else if( slideAutoSlide ) {
autoSlide = parseInt( slideAutoSlide, 10 );
}
else if( parentAutoSlide ) {
autoSlide = parseInt( parentAutoSlide, 10 );
}
else {
autoSlide = config.autoSlide;
}
// If there are media elements with data-autoplay,
// automatically set the autoSlide duration to the
// length of that media. Not applicable if the slide
// is divided up into fragments.
// playbackRate is accounted for in the duration.
if( currentSlide.querySelectorAll( '.fragment' ).length === 0 ) {
toArray( currentSlide.querySelectorAll( 'video, audio' ) ).forEach( el => {
if( el.hasAttribute( 'data-autoplay' ) ) {
if( autoSlide && (el.duration * 1000 / el.playbackRate ) > autoSlide ) {
autoSlide = ( el.duration * 1000 / el.playbackRate ) + 1000;
}
}
} );
}
// Cue the next auto-slide if:
// - There is an autoSlide value
// - Auto-sliding isn't paused by the user
// - The presentation isn't paused
// - The overview isn't active
// - The presentation isn't over
if( autoSlide && !autoSlidePaused && !isPaused() && !overview.isActive() && ( !isLastSlide() || fragments.availableRoutes().next || config.loop === true ) ) {
autoSlideTimeout = setTimeout( () => {
if( typeof config.autoSlideMethod === 'function' ) {
config.autoSlideMethod()
}
else {
navigateNext();
}
cueAutoSlide();
}, autoSlide );
autoSlideStartTime = Date.now();
}
if( autoSlidePlayer ) {
autoSlidePlayer.setPlaying( autoSlideTimeout !== -1 );
}
}
}
/**
* Cancels any ongoing request to auto-slide.
*/
function cancelAutoSlide() {
clearTimeout( autoSlideTimeout );
autoSlideTimeout = -1;
}
function pauseAutoSlide() {
if( autoSlide && !autoSlidePaused ) {
autoSlidePaused = true;
dispatchEvent({ type: 'autoslidepaused' });
clearTimeout( autoSlideTimeout );
if( autoSlidePlayer ) {
autoSlidePlayer.setPlaying( false );
}
}
}
function resumeAutoSlide() {
if( autoSlide && autoSlidePaused ) {
autoSlidePaused = false;
dispatchEvent({ type: 'autoslideresumed' });
cueAutoSlide();
}
}
function navigateLeft() {
hasNavigatedHorizontally = true;
// Reverse for RTL
if( config.rtl ) {
if( ( overview.isActive() || fragments.next() === false ) && availableRoutes().left ) {
slide( indexh + 1, config.navigationMode === 'grid' ? indexv : undefined );
}
}
// Normal navigation
else if( ( overview.isActive() || fragments.prev() === false ) && availableRoutes().left ) {
slide( indexh - 1, config.navigationMode === 'grid' ? indexv : undefined );
}
}
function navigateRight() {
hasNavigatedHorizontally = true;
// Reverse for RTL
if( config.rtl ) {
if( ( overview.isActive() || fragments.prev() === false ) && availableRoutes().right ) {
slide( indexh - 1, config.navigationMode === 'grid' ? indexv : undefined );
}
}
// Normal navigation
else if( ( overview.isActive() || fragments.next() === false ) && availableRoutes().right ) {
slide( indexh + 1, config.navigationMode === 'grid' ? indexv : undefined );
}
}
function navigateUp() {
// Prioritize hiding fragments
if( ( overview.isActive() || fragments.prev() === false ) && availableRoutes().up ) {
slide( indexh, indexv - 1 );
}
}
function navigateDown() {
hasNavigatedVertically = true;
// Prioritize revealing fragments
if( ( overview.isActive() || fragments.next() === false ) && availableRoutes().down ) {
slide( indexh, indexv + 1 );
}
}
/**
* Navigates backwards, prioritized in the following order:
* 1) Previous fragment
* 2) Previous vertical slide
* 3) Previous horizontal slide
*/
function navigatePrev() {
// Prioritize revealing fragments
if( fragments.prev() === false ) {
if( availableRoutes().up ) {
navigateUp();
}
else {
// Fetch the previous horizontal slide, if there is one
let previousSlide;
if( config.rtl ) {
previousSlide = toArray( dom.wrapper.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR + '.future' ) ).pop();
}
else {
previousSlide = toArray( dom.wrapper.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR + '.past' ) ).pop();
}
if( previousSlide ) {
let v = ( previousSlide.querySelectorAll( 'section' ).length - 1 ) || undefined;
let h = indexh - 1;
slide( h, v );
}
}
}
}
/**
* The reverse of #navigatePrev().
*/
function navigateNext() {
hasNavigatedHorizontally = true;
hasNavigatedVertically = true;
// Prioritize revealing fragments
if( fragments.next() === false ) {
let routes = availableRoutes();
// When looping is enabled `routes.down` is always available
// so we need a separate check for when we've reached the
// end of a stack and should move horizontally
if( routes.down && routes.right && config.loop && isLastVerticalSlide( currentSlide ) ) {
routes.down = false;
}
if( routes.down ) {
navigateDown();
}
else if( config.rtl ) {
navigateLeft();
}
else {
navigateRight();
}
}
}
// --------------------------------------------------------------------//
// ----------------------------- EVENTS -------------------------------//
// --------------------------------------------------------------------//
/**
* Called by all event handlers that are based on user
* input.
*
* @param {object} [event]
*/
function onUserInput( event ) {
if( config.autoSlideStoppable ) {
pauseAutoSlide();
}
}
/**
* Called whenever there is mouse input at the document level
* to determine if the cursor is active or not.
*
* @param {object} event
*/
function onDocumentCursorActive( event ) {
showCursor();
clearTimeout( cursorInactiveTimeout );
cursorInactiveTimeout = setTimeout( hideCursor, config.hideCursorTime );
}
/**
* Handles mouse wheel scrolling, throttled to avoid skipping
* multiple slides.
*
* @param {object} event
*/
function onDocumentMouseScroll( event ) {
if( Date.now() - lastMouseWheelStep > 600 ) {
lastMouseWheelStep = Date.now();
let delta = event.detail || -event.wheelDelta;
if( delta > 0 ) {
navigateNext();
}
else if( delta < 0 ) {
navigatePrev();
}
}
}
/**
* Clicking on the progress bar results in a navigation to the
* closest approximate horizontal slide using this equation:
*
* ( clickX / presentationWidth ) * numberOfSlides
*
* @param {object} event
*/
function onProgressClicked( event ) {
onUserInput( event );
event.preventDefault();
let slidesTotal = getHorizontalSlides().length;
let slideIndex = Math.floor( ( event.clientX / dom.wrapper.offsetWidth ) * slidesTotal );
if( config.rtl ) {
slideIndex = slidesTotal - slideIndex;
}
slide( slideIndex );
}
/**
* Event handler for navigation control buttons.
*/
function onNavigateLeftClicked( event ) { event.preventDefault(); onUserInput(); config.navigationMode === 'linear' ? navigatePrev() : navigateLeft(); }
function onNavigateRightClicked( event ) { event.preventDefault(); onUserInput(); config.navigationMode === 'linear' ? navigateNext() : navigateRight(); }
function onNavigateUpClicked( event ) { event.preventDefault(); onUserInput(); navigateUp(); }
function onNavigateDownClicked( event ) { event.preventDefault(); onUserInput(); navigateDown(); }
function onNavigatePrevClicked( event ) { event.preventDefault(); onUserInput(); navigatePrev(); }
function onNavigateNextClicked( event ) { event.preventDefault(); onUserInput(); navigateNext(); }
/**
* Handler for the window level 'hashchange' event.
*
* @param {object} [event]
*/
function onWindowHashChange( event ) {
location.readURL();
}
/**
* Handler for the window level 'resize' event.
*
* @param {object} [event]
*/
function onWindowResize( event ) {
layout();
}
/**
* Handle for the window level 'visibilitychange' event.
*
* @param {object} [event]
*/
function onPageVisibilityChange( event ) {
// If, after clicking a link or similar and we're coming back,
// focus the document.body to ensure we can use keyboard shortcuts
if( document.hidden === false && document.activeElement !== document.body ) {
// Not all elements support .blur() - SVGs among them.
if( typeof document.activeElement.blur === 'function' ) {
document.activeElement.blur();
}
document.body.focus();
}
}
/**
* Handles clicks on links that are set to preview in the
* iframe overlay.
*
* @param {object} event
*/
function onPreviewLinkClicked( event ) {
if( event.currentTarget && event.currentTarget.hasAttribute( 'href' ) ) {
let url = event.currentTarget.getAttribute( 'href' );
if( url ) {
showPreview( url );
event.preventDefault();
}
}
}
/**
* Handles click on the auto-sliding controls element.
*
* @param {object} [event]
*/
function onAutoSlidePlayerClick( event ) {
// Replay
if( isLastSlide() && config.loop === false ) {
slide( 0, 0 );
resumeAutoSlide();
}
// Resume
else if( autoSlidePaused ) {
resumeAutoSlide();
}
// Pause
else {
pauseAutoSlide();
}
}
// --------------------------------------------------------------------//
// ------------------------------- API --------------------------------//
// --------------------------------------------------------------------//
return extend( Reveal, {
VERSION,
initialize,
configure,
sync,
syncSlide,
syncFragments,
// Navigation methods
slide,
left: navigateLeft,
right: navigateRight,
up: navigateUp,
down: navigateDown,
prev: navigatePrev,
next: navigateNext,
// Deprecated aliases
navigateTo: slide,
navigateLeft: navigateLeft,
navigateRight: navigateRight,
navigateUp: navigateUp,
navigateDown: navigateDown,
navigatePrev: navigatePrev,
navigateNext: navigateNext,
// Fragment methods
navigateFragment: fragments.goto.bind( fragments ),
prevFragment: fragments.prev.bind( fragments ),
nextFragment: fragments.next.bind( fragments ),
// Forward event binding to the reveal DOM element
addEventListener: ( type, listener, useCapture ) => {
Reveal.getRevealElement().addEventListener( type, listener, useCapture );
},
removeEventListener: ( type, listener, useCapture ) => {
Reveal.getRevealElement().removeEventListener( type, listener, useCapture );
},
// Forces an update in slide layout
layout,
// Randomizes the order of slides
shuffle,
// Returns an object with the available routes as booleans (left/right/top/bottom)
availableRoutes,
// Returns an object with the available fragments as booleans (prev/next)
availableFragments: fragments.availableRoutes.bind( fragments ),
// Toggles a help overlay with keyboard shortcuts
toggleHelp,
// Toggles the overview mode on/off
toggleOverview: overview.toggle.bind( overview ),
// Toggles the "black screen" mode on/off
togglePause,
// Toggles the auto slide mode on/off
toggleAutoSlide,
// Slide navigation checks
isFirstSlide,
isLastSlide,
isLastVerticalSlide,
isVerticalSlide,
// State checks
isOverview: overview.isActive.bind( overview ),
isPaused,
isAutoSliding,
isSpeakerNotes,
isPrintingPDF,
// Slide preloading
loadSlide: slideContent.load.bind( slideContent ),
unloadSlide: slideContent.unload.bind( slideContent ),
// Adds or removes all internal event listeners (such as keyboard)
addEventListeners,
removeEventListeners,
dispatchEvent,
// Facility for persisting and restoring the presentation state
getState,
setState,
// Presentation progress
getSlidePastCount,
// Presentation progress on range of 0-1
getProgress,
// Returns the indices of the current, or specified, slide
getIndices,
// Returns an Array of all slides
getSlides,
// Returns an Array of objects representing the attributes on
// the slides
getSlidesAttributes,
// Returns the total number of slides
getTotalSlides,
// Returns the slide element at the specified index
getSlide,
// Returns the slide background element at the specified index
getSlideBackground,
// Returns the speaker notes string for a slide, or null
getSlideNotes,
// Returns an array with all horizontal/vertical slides in the deck
getHorizontalSlides,
getVerticalSlides,
// Checks if the presentation contains two or more
// horizontal/vertical slides
hasHorizontalSlides,
hasVerticalSlides,
// Adds/removes a custom key binding
addKeyBinding: keyboard.addKeyBinding.bind( keyboard ),
removeKeyBinding: keyboard.removeKeyBinding.bind( keyboard ),
// Programmatically triggers a keyboard event
triggerKey: keyboard.triggerKey.bind( keyboard ),
// Registers a new shortcut to include in the help overlay
registerKeyboardShortcut: keyboard.registerKeyboardShortcut.bind( keyboard ),
// API for registering and retrieving plugins
registerPlugin: plugins.registerPlugin.bind( plugins ),
hasPlugin: plugins.hasPlugin.bind( plugins ),
getPlugin: plugins.getPlugin.bind( plugins ),
getPlugins: plugins.getRegisteredPlugins.bind( plugins ),
getComputedSlideSize,
// Returns the previous slide element, may be null
getPreviousSlide: () => previousSlide,
// Returns the current slide element
getCurrentSlide: () => currentSlide,
// Returns the current scale of the presentation content
getScale: () => scale,
// Returns the current configuration object
getConfig: () => config,
// Helper method, retrieves query string as a key:value map
getQueryHash,
// Returns the top-level DOM element
getRevealElement: () => dom.wrapper || document.querySelector( '.reveal' ),
getSlidesElement: () => dom.slides,
getBackgroundsElement: () => dom.background,
// Checks if reveal.js has been loaded and is ready for use
isReady: () => ready,
// The following API methods are primarily intended for use
// by reveal.js controllers
// Methods for announcing content to screen readers
announceStatus,
getStatusText,
location,
overview,
slideContent,
onUserInput,
closeOverlay,
updateControls,
updateProgress,
updateSlidesVisibility,
transformSlides,
cueAutoSlide,
cancelAutoSlide
} );
};