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|
<!--
NOTE: You need to build the notes plugin after making changes to this file.
-->
<html lang="en">
<head>
<meta charset="utf-8">
<title>reveal.js - Speaker View</title>
<style>
body {
font-family: Helvetica;
font-size: 18px;
}
#current-slide,
#upcoming-slide,
#speaker-controls {
padding: 6px;
box-sizing: border-box;
-moz-box-sizing: border-box;
}
#current-slide iframe,
#upcoming-slide iframe {
width: 100%;
height: 100%;
border: 1px solid #ddd;
}
#current-slide .label,
#upcoming-slide .label {
position: absolute;
top: 10px;
left: 10px;
z-index: 2;
}
#connection-status {
position: absolute;
top: 0;
left: 0;
width: 100%;
height: 100%;
z-index: 20;
padding: 30% 20% 20% 20%;
font-size: 18px;
color: #222;
background: #fff;
text-align: center;
box-sizing: border-box;
line-height: 1.4;
}
.overlay-element {
height: 34px;
line-height: 34px;
padding: 0 10px;
text-shadow: none;
background: rgba( 220, 220, 220, 0.8 );
color: #222;
font-size: 14px;
}
.overlay-element.interactive:hover {
background: rgba( 220, 220, 220, 1 );
}
#current-slide {
position: absolute;
width: 60%;
height: 100%;
top: 0;
left: 0;
padding-right: 0;
}
#upcoming-slide {
position: absolute;
width: 40%;
height: 40%;
right: 0;
top: 0;
}
/* Speaker controls */
#speaker-controls {
position: absolute;
top: 40%;
right: 0;
width: 40%;
height: 60%;
overflow: auto;
font-size: 18px;
}
.speaker-controls-time.hidden,
.speaker-controls-notes.hidden {
display: none;
}
.speaker-controls-time .label,
.speaker-controls-pace .label,
.speaker-controls-notes .label {
text-transform: uppercase;
font-weight: normal;
font-size: 0.66em;
color: #666;
margin: 0;
}
.speaker-controls-time, .speaker-controls-pace {
border-bottom: 1px solid rgba( 200, 200, 200, 0.5 );
margin-bottom: 10px;
padding: 10px 16px;
padding-bottom: 20px;
cursor: pointer;
}
.speaker-controls-time .reset-button {
opacity: 0;
float: right;
color: #666;
text-decoration: none;
}
.speaker-controls-time:hover .reset-button {
opacity: 1;
}
.speaker-controls-time .timer,
.speaker-controls-time .clock {
width: 50%;
}
.speaker-controls-time .timer,
.speaker-controls-time .clock,
.speaker-controls-time .pacing .hours-value,
.speaker-controls-time .pacing .minutes-value,
.speaker-controls-time .pacing .seconds-value {
font-size: 1.9em;
}
.speaker-controls-time .timer {
float: left;
}
.speaker-controls-time .clock {
float: right;
text-align: right;
}
.speaker-controls-time span.mute {
opacity: 0.3;
}
.speaker-controls-time .pacing-title {
margin-top: 5px;
}
.speaker-controls-time .pacing.ahead {
color: blue;
}
.speaker-controls-time .pacing.on-track {
color: green;
}
.speaker-controls-time .pacing.behind {
color: red;
}
.speaker-controls-notes {
padding: 10px 16px;
}
.speaker-controls-notes .value {
margin-top: 5px;
line-height: 1.4;
font-size: 1.2em;
}
/* Layout selector */
#speaker-layout {
position: absolute;
top: 10px;
right: 10px;
color: #222;
z-index: 10;
}
#speaker-layout select {
position: absolute;
width: 100%;
height: 100%;
top: 0;
left: 0;
border: 0;
box-shadow: 0;
cursor: pointer;
opacity: 0;
font-size: 1em;
background-color: transparent;
-moz-appearance: none;
-webkit-appearance: none;
-webkit-tap-highlight-color: rgba(0, 0, 0, 0);
}
#speaker-layout select:focus {
outline: none;
box-shadow: none;
}
.clear {
clear: both;
}
/* Speaker layout: Wide */
body[data-speaker-layout="wide"] #current-slide,
body[data-speaker-layout="wide"] #upcoming-slide {
width: 50%;
height: 45%;
padding: 6px;
}
body[data-speaker-layout="wide"] #current-slide {
top: 0;
left: 0;
}
body[data-speaker-layout="wide"] #upcoming-slide {
top: 0;
left: 50%;
}
body[data-speaker-layout="wide"] #speaker-controls {
top: 45%;
left: 0;
width: 100%;
height: 50%;
font-size: 1.25em;
}
/* Speaker layout: Tall */
body[data-speaker-layout="tall"] #current-slide,
body[data-speaker-layout="tall"] #upcoming-slide {
width: 45%;
height: 50%;
padding: 6px;
}
body[data-speaker-layout="tall"] #current-slide {
top: 0;
left: 0;
}
body[data-speaker-layout="tall"] #upcoming-slide {
top: 50%;
left: 0;
}
body[data-speaker-layout="tall"] #speaker-controls {
padding-top: 40px;
top: 0;
left: 45%;
width: 55%;
height: 100%;
font-size: 1.25em;
}
/* Speaker layout: Notes only */
body[data-speaker-layout="notes-only"] #current-slide,
body[data-speaker-layout="notes-only"] #upcoming-slide {
display: none;
}
body[data-speaker-layout="notes-only"] #speaker-controls {
padding-top: 40px;
top: 0;
left: 0;
width: 100%;
height: 100%;
font-size: 1.25em;
}
@media screen and (max-width: 1080px) {
body[data-speaker-layout="default"] #speaker-controls {
font-size: 16px;
}
}
@media screen and (max-width: 900px) {
body[data-speaker-layout="default"] #speaker-controls {
font-size: 14px;
}
}
@media screen and (max-width: 800px) {
body[data-speaker-layout="default"] #speaker-controls {
font-size: 12px;
}
}
</style>
</head>
<body>
<div id="connection-status">Loading speaker view...</div>
<div id="current-slide"></div>
<div id="upcoming-slide"><span class="overlay-element label">Upcoming</span></div>
<div id="speaker-controls">
<div class="speaker-controls-time">
<h4 class="label">Time <span class="reset-button">Click to Reset</span></h4>
<div class="clock">
<span class="clock-value">0:00 AM</span>
</div>
<div class="timer">
<span class="hours-value">00</span><span class="minutes-value">:00</span><span class="seconds-value">:00</span>
</div>
<div class="clear"></div>
<h4 class="label pacing-title" style="display: none">Pacing – Time to finish current slide</h4>
<div class="pacing" style="display: none">
<span class="hours-value">00</span><span class="minutes-value">:00</span><span class="seconds-value">:00</span>
</div>
</div>
<div class="speaker-controls-notes hidden">
<h4 class="label">Notes</h4>
<div class="value"></div>
</div>
</div>
<div id="speaker-layout" class="overlay-element interactive">
<span class="speaker-layout-label"></span>
<select class="speaker-layout-dropdown"></select>
</div>
<script>
(function() {
var notes,
notesValue,
currentState,
currentSlide,
upcomingSlide,
layoutLabel,
layoutDropdown,
pendingCalls = {},
lastRevealApiCallId = 0,
connected = false
var connectionStatus = document.querySelector( '#connection-status' );
var SPEAKER_LAYOUTS = {
'default': 'Default',
'wide': 'Wide',
'tall': 'Tall',
'notes-only': 'Notes only'
};
setupLayout();
let openerOrigin;
try {
openerOrigin = window.opener.location.origin;
}
catch ( error ) { console.warn( error ) }
// In order to prevent XSS, the speaker view will only run if its
// opener has the same origin as itself
if( window.location.origin !== openerOrigin ) {
connectionStatus.innerHTML = 'Cross origin error.<br>The speaker window can only be opened from the same origin.';
return;
}
var connectionTimeout = setTimeout( function() {
connectionStatus.innerHTML = 'Error connecting to main window.<br>Please try closing and reopening the speaker view.';
}, 5000 );
window.addEventListener( 'message', function( event ) {
// Validate the origin of all messages to avoid parsing messages
// that aren't meant for us. Ignore when running off file:// so
// that the speaker view continues to work without a web server.
if( window.location.origin !== event.origin && window.location.origin !== 'file://' ) {
return
}
clearTimeout( connectionTimeout );
connectionStatus.style.display = 'none';
var data = JSON.parse( event.data );
// The overview mode is only useful to the reveal.js instance
// where navigation occurs so we don't sync it
if( data.state ) delete data.state.overview;
// Messages sent by the notes plugin inside of the main window
if( data && data.namespace === 'reveal-notes' ) {
if( data.type === 'connect' ) {
handleConnectMessage( data );
}
else if( data.type === 'state' ) {
handleStateMessage( data );
}
else if( data.type === 'return' ) {
pendingCalls[data.callId](data.result);
delete pendingCalls[data.callId];
}
}
// Messages sent by the reveal.js inside of the current slide preview
else if( data && data.namespace === 'reveal' ) {
if( /ready/.test( data.eventName ) ) {
// Send a message back to notify that the handshake is complete
window.opener.postMessage( JSON.stringify({ namespace: 'reveal-notes', type: 'connected'} ), '*' );
}
else if( /slidechanged|fragmentshown|fragmenthidden|paused|resumed/.test( data.eventName ) && currentState !== JSON.stringify( data.state ) ) {
dispatchStateToMainWindow( data.state );
}
}
} );
/**
* Updates the presentation in the main window to match the state
* of the presentation in the notes window.
*/
const dispatchStateToMainWindow = debounce(( state ) => {
window.opener.postMessage( JSON.stringify({ method: 'setState', args: [ state ]} ), '*' );
}, 500);
/**
* Asynchronously calls the Reveal.js API of the main frame.
*/
function callRevealApi( methodName, methodArguments, callback ) {
var callId = ++lastRevealApiCallId;
pendingCalls[callId] = callback;
window.opener.postMessage( JSON.stringify( {
namespace: 'reveal-notes',
type: 'call',
callId: callId,
methodName: methodName,
arguments: methodArguments
} ), '*' );
}
/**
* Called when the main window is trying to establish a
* connection.
*/
function handleConnectMessage( data ) {
if( connected === false ) {
connected = true;
setupIframes( data );
setupKeyboard();
setupNotes();
setupTimer();
setupHeartbeat();
}
}
/**
* Called when the main window sends an updated state.
*/
function handleStateMessage( data ) {
// Store the most recently set state to avoid circular loops
// applying the same state
currentState = JSON.stringify( data.state );
// No need for updating the notes in case of fragment changes
if ( data.notes ) {
notes.classList.remove( 'hidden' );
notesValue.style.whiteSpace = data.whitespace;
if( data.markdown ) {
notesValue.innerHTML = marked( data.notes );
}
else {
notesValue.innerHTML = data.notes;
}
}
else {
notes.classList.add( 'hidden' );
}
// Update the note slides
currentSlide.contentWindow.postMessage( JSON.stringify({ method: 'setState', args: [ data.state ] }), '*' );
upcomingSlide.contentWindow.postMessage( JSON.stringify({ method: 'setState', args: [ data.state ] }), '*' );
upcomingSlide.contentWindow.postMessage( JSON.stringify({ method: 'next' }), '*' );
}
// Limit to max one state update per X ms
handleStateMessage = debounce( handleStateMessage, 200 );
/**
* Forward keyboard events to the current slide window.
* This enables keyboard events to work even if focus
* isn't set on the current slide iframe.
*
* Block F5 default handling, it reloads and disconnects
* the speaker notes window.
*/
function setupKeyboard() {
document.addEventListener( 'keydown', function( event ) {
if( event.keyCode === 116 || ( event.metaKey && event.keyCode === 82 ) ) {
event.preventDefault();
return false;
}
currentSlide.contentWindow.postMessage( JSON.stringify({ method: 'triggerKey', args: [ event.keyCode ] }), '*' );
} );
}
/**
* Creates the preview iframes.
*/
function setupIframes( data ) {
var params = [
'receiver',
'progress=false',
'history=false',
'transition=none',
'autoSlide=0',
'backgroundTransition=none'
].join( '&' );
var urlSeparator = /\?/.test(data.url) ? '&' : '?';
var hash = '#/' + data.state.indexh + '/' + data.state.indexv;
var currentURL = data.url + urlSeparator + params + '&scrollActivationWidth=false&postMessageEvents=true' + hash;
var upcomingURL = data.url + urlSeparator + params + '&scrollActivationWidth=false&controls=false' + hash;
currentSlide = document.createElement( 'iframe' );
currentSlide.setAttribute( 'width', 1280 );
currentSlide.setAttribute( 'height', 1024 );
currentSlide.setAttribute( 'src', currentURL );
document.querySelector( '#current-slide' ).appendChild( currentSlide );
upcomingSlide = document.createElement( 'iframe' );
upcomingSlide.setAttribute( 'width', 640 );
upcomingSlide.setAttribute( 'height', 512 );
upcomingSlide.setAttribute( 'src', upcomingURL );
document.querySelector( '#upcoming-slide' ).appendChild( upcomingSlide );
}
/**
* Setup the notes UI.
*/
function setupNotes() {
notes = document.querySelector( '.speaker-controls-notes' );
notesValue = document.querySelector( '.speaker-controls-notes .value' );
}
/**
* We send out a heartbeat at all times to ensure we can
* reconnect with the main presentation window after reloads.
*/
function setupHeartbeat() {
setInterval( () => {
window.opener.postMessage( JSON.stringify({ namespace: 'reveal-notes', type: 'heartbeat'} ), '*' );
}, 1000 );
}
function getTimings( callback ) {
callRevealApi( 'getSlidesAttributes', [], function ( slideAttributes ) {
callRevealApi( 'getConfig', [], function ( config ) {
var totalTime = config.totalTime;
var minTimePerSlide = config.minimumTimePerSlide || 0;
var defaultTiming = config.defaultTiming;
if ((defaultTiming == null) && (totalTime == null)) {
callback(null);
return;
}
// Setting totalTime overrides defaultTiming
if (totalTime) {
defaultTiming = 0;
}
var timings = [];
for ( var i in slideAttributes ) {
var slide = slideAttributes[ i ];
var timing = defaultTiming;
if( slide.hasOwnProperty( 'data-timing' )) {
var t = slide[ 'data-timing' ];
timing = parseInt(t);
if( isNaN(timing) ) {
console.warn("Could not parse timing '" + t + "' of slide " + i + "; using default of " + defaultTiming);
timing = defaultTiming;
}
}
timings.push(timing);
}
if ( totalTime ) {
// After we've allocated time to individual slides, we summarize it and
// subtract it from the total time
var remainingTime = totalTime - timings.reduce( function(a, b) { return a + b; }, 0 );
// The remaining time is divided by the number of slides that have 0 seconds
// allocated at the moment, giving the average time-per-slide on the remaining slides
var remainingSlides = (timings.filter( function(x) { return x == 0 }) ).length
var timePerSlide = Math.round( remainingTime / remainingSlides, 0 )
// And now we replace every zero-value timing with that average
timings = timings.map( function(x) { return (x==0 ? timePerSlide : x) } );
}
var slidesUnderMinimum = timings.filter( function(x) { return (x < minTimePerSlide) } ).length
if ( slidesUnderMinimum ) {
message = "The pacing time for " + slidesUnderMinimum + " slide(s) is under the configured minimum of " + minTimePerSlide + " seconds. Check the data-timing attribute on individual slides, or consider increasing the totalTime or minimumTimePerSlide configuration options (or removing some slides).";
alert(message);
}
callback( timings );
} );
} );
}
/**
* Return the number of seconds allocated for presenting
* all slides up to and including this one.
*/
function getTimeAllocated( timings, callback ) {
callRevealApi( 'getSlidePastCount', [], function ( currentSlide ) {
var allocated = 0;
for (var i in timings.slice(0, currentSlide + 1)) {
allocated += timings[i];
}
callback( allocated );
} );
}
/**
* Create the timer and clock and start updating them
* at an interval.
*/
function setupTimer() {
var start = new Date(),
timeEl = document.querySelector( '.speaker-controls-time' ),
clockEl = timeEl.querySelector( '.clock-value' ),
hoursEl = timeEl.querySelector( '.hours-value' ),
minutesEl = timeEl.querySelector( '.minutes-value' ),
secondsEl = timeEl.querySelector( '.seconds-value' ),
pacingTitleEl = timeEl.querySelector( '.pacing-title' ),
pacingEl = timeEl.querySelector( '.pacing' ),
pacingHoursEl = pacingEl.querySelector( '.hours-value' ),
pacingMinutesEl = pacingEl.querySelector( '.minutes-value' ),
pacingSecondsEl = pacingEl.querySelector( '.seconds-value' );
var timings = null;
getTimings( function ( _timings ) {
timings = _timings;
if (_timings !== null) {
pacingTitleEl.style.removeProperty('display');
pacingEl.style.removeProperty('display');
}
// Update once directly
_updateTimer();
// Then update every second
setInterval( _updateTimer, 1000 );
} );
function _resetTimer() {
if (timings == null) {
start = new Date();
_updateTimer();
}
else {
// Reset timer to beginning of current slide
getTimeAllocated( timings, function ( slideEndTimingSeconds ) {
var slideEndTiming = slideEndTimingSeconds * 1000;
callRevealApi( 'getSlidePastCount', [], function ( currentSlide ) {
var currentSlideTiming = timings[currentSlide] * 1000;
var previousSlidesTiming = slideEndTiming - currentSlideTiming;
var now = new Date();
start = new Date(now.getTime() - previousSlidesTiming);
_updateTimer();
} );
} );
}
}
timeEl.addEventListener( 'click', function() {
_resetTimer();
return false;
} );
function _displayTime( hrEl, minEl, secEl, time) {
var sign = Math.sign(time) == -1 ? "-" : "";
time = Math.abs(Math.round(time / 1000));
var seconds = time % 60;
var minutes = Math.floor( time / 60 ) % 60 ;
var hours = Math.floor( time / ( 60 * 60 )) ;
hrEl.innerHTML = sign + zeroPadInteger( hours );
if (hours == 0) {
hrEl.classList.add( 'mute' );
}
else {
hrEl.classList.remove( 'mute' );
}
minEl.innerHTML = ':' + zeroPadInteger( minutes );
if (hours == 0 && minutes == 0) {
minEl.classList.add( 'mute' );
}
else {
minEl.classList.remove( 'mute' );
}
secEl.innerHTML = ':' + zeroPadInteger( seconds );
}
function _updateTimer() {
var diff, hours, minutes, seconds,
now = new Date();
diff = now.getTime() - start.getTime();
clockEl.innerHTML = now.toLocaleTimeString( 'en-US', { hour12: true, hour: '2-digit', minute:'2-digit' } );
_displayTime( hoursEl, minutesEl, secondsEl, diff );
if (timings !== null) {
_updatePacing(diff);
}
}
function _updatePacing(diff) {
getTimeAllocated( timings, function ( slideEndTimingSeconds ) {
var slideEndTiming = slideEndTimingSeconds * 1000;
callRevealApi( 'getSlidePastCount', [], function ( currentSlide ) {
var currentSlideTiming = timings[currentSlide] * 1000;
var timeLeftCurrentSlide = slideEndTiming - diff;
if (timeLeftCurrentSlide < 0) {
pacingEl.className = 'pacing behind';
}
else if (timeLeftCurrentSlide < currentSlideTiming) {
pacingEl.className = 'pacing on-track';
}
else {
pacingEl.className = 'pacing ahead';
}
_displayTime( pacingHoursEl, pacingMinutesEl, pacingSecondsEl, timeLeftCurrentSlide );
} );
} );
}
}
/**
* Sets up the speaker view layout and layout selector.
*/
function setupLayout() {
layoutDropdown = document.querySelector( '.speaker-layout-dropdown' );
layoutLabel = document.querySelector( '.speaker-layout-label' );
// Render the list of available layouts
for( var id in SPEAKER_LAYOUTS ) {
var option = document.createElement( 'option' );
option.setAttribute( 'value', id );
option.textContent = SPEAKER_LAYOUTS[ id ];
layoutDropdown.appendChild( option );
}
// Monitor the dropdown for changes
layoutDropdown.addEventListener( 'change', function( event ) {
setLayout( layoutDropdown.value );
}, false );
// Restore any currently persisted layout
setLayout( getLayout() );
}
/**
* Sets a new speaker view layout. The layout is persisted
* in local storage.
*/
function setLayout( value ) {
var title = SPEAKER_LAYOUTS[ value ];
layoutLabel.innerHTML = 'Layout' + ( title ? ( ': ' + title ) : '' );
layoutDropdown.value = value;
document.body.setAttribute( 'data-speaker-layout', value );
// Persist locally
if( supportsLocalStorage() ) {
window.localStorage.setItem( 'reveal-speaker-layout', value );
}
}
/**
* Returns the ID of the most recently set speaker layout
* or our default layout if none has been set.
*/
function getLayout() {
if( supportsLocalStorage() ) {
var layout = window.localStorage.getItem( 'reveal-speaker-layout' );
if( layout ) {
return layout;
}
}
// Default to the first record in the layouts hash
for( var id in SPEAKER_LAYOUTS ) {
return id;
}
}
function supportsLocalStorage() {
try {
localStorage.setItem('test', 'test');
localStorage.removeItem('test');
return true;
}
catch( e ) {
return false;
}
}
function zeroPadInteger( num ) {
var str = '00' + parseInt( num );
return str.substring( str.length - 2 );
}
/**
* Limits the frequency at which a function can be called.
*/
function debounce( fn, ms ) {
var lastTime = 0,
timeout;
return function() {
var args = arguments;
var context = this;
clearTimeout( timeout );
var timeSinceLastCall = Date.now() - lastTime;
if( timeSinceLastCall > ms ) {
fn.apply( context, args );
lastTime = Date.now();
}
else {
timeout = setTimeout( function() {
fn.apply( context, args );
lastTime = Date.now();
}, ms - timeSinceLastCall );
}
}
}
})();
</script>
</body>
</html>
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