js/controllers/keyboard.js
import { enterFullscreen } from '../utils/util.js'
/**
* Handles all reveal.js keyboard interactions.
*/
export default class Keyboard {
constructor( Reveal ) {
this.Reveal = Reveal;
// A key:value map of keyboard keys and descriptions of
// the actions they trigger
this.shortcuts = {};
// Holds custom key code mappings
this.bindings = {};
this.onDocumentKeyDown = this.onDocumentKeyDown.bind( this );
}
/**
* Called when the reveal.js config is updated.
*/
configure( config, oldConfig ) {
if( config.navigationMode === 'linear' ) {
this.shortcuts['→ , ↓ , SPACE , N , L , J'] = 'Next slide';
this.shortcuts['← , ↑ , P , H , K'] = 'Previous slide';
}
else {
this.shortcuts['N , SPACE'] = 'Next slide';
this.shortcuts['P , Shift SPACE'] = 'Previous slide';
this.shortcuts['← , H'] = 'Navigate left';
this.shortcuts['→ , L'] = 'Navigate right';
this.shortcuts['↑ , K'] = 'Navigate up';
this.shortcuts['↓ , J'] = 'Navigate down';
}
this.shortcuts['Alt + ←/↑/→/↓'] = 'Navigate without fragments';
this.shortcuts['Shift + ←/↑/→/↓'] = 'Jump to first/last slide';
this.shortcuts['B , .'] = 'Pause';
this.shortcuts['F'] = 'Fullscreen';
this.shortcuts['G'] = 'Jump to slide';
this.shortcuts['ESC, O'] = 'Slide overview';
}
/**
* Starts listening for keyboard events.
*/
bind() {
document.addEventListener( 'keydown', this.onDocumentKeyDown, false );
}
/**
* Stops listening for keyboard events.
*/
unbind() {
document.removeEventListener( 'keydown', this.onDocumentKeyDown, false );
}
/**
* Add a custom key binding with optional description to
* be added to the help screen.
*/
addKeyBinding( binding, callback ) {
if( typeof binding === 'object' && binding.keyCode ) {
this.bindings[binding.keyCode] = {
callback: callback,
key: binding.key,
description: binding.description
};
}
else {
this.bindings[binding] = {
callback: callback,
key: null,
description: null
};
}
}
/**
* Removes the specified custom key binding.
*/
removeKeyBinding( keyCode ) {
delete this.bindings[keyCode];
}
/**
* Programmatically triggers a keyboard event
*
* @param {int} keyCode
*/
triggerKey( keyCode ) {
this.onDocumentKeyDown( { keyCode } );
}
/**
* Registers a new shortcut to include in the help overlay
*
* @param {String} key
* @param {String} value
*/
registerKeyboardShortcut( key, value ) {
this.shortcuts[key] = value;
}
getShortcuts() {
return this.shortcuts;
}
getBindings() {
return this.bindings;
}
/**
* Handler for the document level 'keydown' event.
*
* @param {object} event
*/
onDocumentKeyDown( event ) {
let config = this.Reveal.getConfig();
// If there's a condition specified and it returns false,
// ignore this event
if( typeof config.keyboardCondition === 'function' && config.keyboardCondition(event) === false ) {
return true;
}
// If keyboardCondition is set, only capture keyboard events
// for embedded decks when they are focused
if( config.keyboardCondition === 'focused' && !this.Reveal.isFocused() ) {
return true;
}
// Shorthand
let keyCode = event.keyCode;
// Remember if auto-sliding was paused so we can toggle it
let autoSlideWasPaused = !this.Reveal.isAutoSliding();
this.Reveal.onUserInput( event );
// Is there a focused element that could be using the keyboard?
let activeElementIsCE = document.activeElement && document.activeElement.isContentEditable === true;
let activeElementIsInput = document.activeElement && document.activeElement.tagName && /input|textarea/i.test( document.activeElement.tagName );
let activeElementIsNotes = document.activeElement && document.activeElement.className && /speaker-notes/i.test( document.activeElement.className);
// Whitelist certain modifiers for slide navigation shortcuts
let keyCodeUsesModifier = [32, 37, 38, 39, 40, 63, 78, 80, 191].indexOf( event.keyCode ) !== -1;
// Prevent all other events when a modifier is pressed
let unusedModifier = !( keyCodeUsesModifier && event.shiftKey || event.altKey ) &&
( event.shiftKey || event.altKey || event.ctrlKey || event.metaKey );
// Disregard the event if there's a focused element or a
// keyboard modifier key is present
if( activeElementIsCE || activeElementIsInput || activeElementIsNotes || unusedModifier ) return;
// While paused only allow resume keyboard events; 'b', 'v', '.'
let resumeKeyCodes = [66,86,190,191,112];
let key;
// Custom key bindings for togglePause should be able to resume
if( typeof config.keyboard === 'object' ) {
for( key in config.keyboard ) {
if( config.keyboard[key] === 'togglePause' ) {
resumeKeyCodes.push( parseInt( key, 10 ) );
}
}
}
if( this.Reveal.isPaused() && resumeKeyCodes.indexOf( keyCode ) === -1 ) {
return false;
}
// Use linear navigation if we're configured to OR if
// the presentation is one-dimensional
let useLinearMode = config.navigationMode === 'linear' || !this.Reveal.hasHorizontalSlides() || !this.Reveal.hasVerticalSlides();
let triggered = false;
// 1. User defined key bindings
if( typeof config.keyboard === 'object' ) {
for( key in config.keyboard ) {
// Check if this binding matches the pressed key
if( parseInt( key, 10 ) === keyCode ) {
let value = config.keyboard[ key ];
// Callback function
if( typeof value === 'function' ) {
value.apply( null, [ event ] );
}
// String shortcuts to reveal.js API
else if( typeof value === 'string' && typeof this.Reveal[ value ] === 'function' ) {
this.Reveal[ value ].call();
}
triggered = true;
}
}
}
// 2. Registered custom key bindings
if( triggered === false ) {
for( key in this.bindings ) {
// Check if this binding matches the pressed key
if( parseInt( key, 10 ) === keyCode ) {
let action = this.bindings[ key ].callback;
// Callback function
if( typeof action === 'function' ) {
action.apply( null, [ event ] );
}
// String shortcuts to reveal.js API
else if( typeof action === 'string' && typeof this.Reveal[ action ] === 'function' ) {
this.Reveal[ action ].call();
}
triggered = true;
}
}
}
// 3. System defined key bindings
if( triggered === false ) {
// Assume true and try to prove false
triggered = true;
// P, PAGE UP
if( keyCode === 80 || keyCode === 33 ) {
this.Reveal.prev({skipFragments: event.altKey});
}
// N, PAGE DOWN
else if( keyCode === 78 || keyCode === 34 ) {
this.Reveal.next({skipFragments: event.altKey});
}
// H, LEFT
else if( keyCode === 72 || keyCode === 37 ) {
if( event.shiftKey ) {
this.Reveal.slide( 0 );
}
else if( !this.Reveal.overview.isActive() && useLinearMode ) {
if( config.rtl ) {
this.Reveal.next({skipFragments: event.altKey});
}
else {
this.Reveal.prev({skipFragments: event.altKey});
}
}
else {
this.Reveal.left({skipFragments: event.altKey});
}
}
// L, RIGHT
else if( keyCode === 76 || keyCode === 39 ) {
if( event.shiftKey ) {
this.Reveal.slide( this.Reveal.getHorizontalSlides().length - 1 );
}
else if( !this.Reveal.overview.isActive() && useLinearMode ) {
if( config.rtl ) {
this.Reveal.prev({skipFragments: event.altKey});
}
else {
this.Reveal.next({skipFragments: event.altKey});
}
}
else {
this.Reveal.right({skipFragments: event.altKey});
}
}
// K, UP
else if( keyCode === 75 || keyCode === 38 ) {
if( event.shiftKey ) {
this.Reveal.slide( undefined, 0 );
}
else if( !this.Reveal.overview.isActive() && useLinearMode ) {
this.Reveal.prev({skipFragments: event.altKey});
}
else {
this.Reveal.up({skipFragments: event.altKey});
}
}
// J, DOWN
else if( keyCode === 74 || keyCode === 40 ) {
if( event.shiftKey ) {
this.Reveal.slide( undefined, Number.MAX_VALUE );
}
else if( !this.Reveal.overview.isActive() && useLinearMode ) {
this.Reveal.next({skipFragments: event.altKey});
}
else {
this.Reveal.down({skipFragments: event.altKey});
}
}
// HOME
else if( keyCode === 36 ) {
this.Reveal.slide( 0 );
}
// END
else if( keyCode === 35 ) {
this.Reveal.slide( this.Reveal.getHorizontalSlides().length - 1 );
}
// SPACE
else if( keyCode === 32 ) {
if( this.Reveal.overview.isActive() ) {
this.Reveal.overview.deactivate();
}
if( event.shiftKey ) {
this.Reveal.prev({skipFragments: event.altKey});
}
else {
this.Reveal.next({skipFragments: event.altKey});
}
}
// TWO-SPOT, SEMICOLON, B, V, PERIOD, LOGITECH PRESENTER TOOLS "BLACK SCREEN" BUTTON
else if( [58, 59, 66, 86, 190].includes( keyCode ) || ( keyCode === 191 && !event.shiftKey ) ) {
this.Reveal.togglePause();
}
// F
else if( keyCode === 70 ) {
enterFullscreen( config.embedded ? this.Reveal.getViewportElement() : document.documentElement );
}
// A
else if( keyCode === 65 ) {
if( config.autoSlideStoppable ) {
this.Reveal.toggleAutoSlide( autoSlideWasPaused );
}
}
// G
else if( keyCode === 71 ) {
if( config.jumpToSlide ) {
this.Reveal.toggleJumpToSlide();
}
}
// ?
else if( ( keyCode === 63 || keyCode === 191 ) && event.shiftKey ) {
this.Reveal.toggleHelp();
}
// F1
else if( keyCode === 112 ) {
this.Reveal.toggleHelp();
}
else {
triggered = false;
}
}
// If the input resulted in a triggered action we should prevent
// the browsers default behavior
if( triggered ) {
event.preventDefault && event.preventDefault();
}
// ESC or O key
else if( keyCode === 27 || keyCode === 79 ) {
if( this.Reveal.closeOverlay() === false ) {
this.Reveal.overview.toggle();
}
event.preventDefault && event.preventDefault();
}
// If auto-sliding is enabled we need to cue up
// another timeout
this.Reveal.cueAutoSlide();
}
}