WordPress/wp-content/themes/twentytwenty/assets/js/index.js

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/* -----------------------------------------------------------------------------------------------
Namespace
--------------------------------------------------------------------------------------------------- */
var twentytwenty = twentytwenty || {};
// Set a default value for scrolled.
twentytwenty.scrolled = 0;
// polyfill closest
// https://developer.mozilla.org/en-US/docs/Web/API/Element/closest#Polyfill
if ( ! Element.prototype.closest ) {
Element.prototype.closest = function( s ) {
var el = this;
do {
if ( el.matches( s ) ) {
return el;
}
el = el.parentElement || el.parentNode;
} while ( el !== null && el.nodeType === 1 );
return null;
};
}
// polyfill forEach
// https://developer.mozilla.org/en-US/docs/Web/API/NodeList/forEach#Polyfill
if ( window.NodeList && ! NodeList.prototype.forEach ) {
NodeList.prototype.forEach = function( callback, thisArg ) {
var i;
var len = this.length;
thisArg = thisArg || window;
for ( i = 0; i < len; i++ ) {
callback.call( thisArg, this[ i ], i, this );
}
};
}
// event "polyfill"
twentytwenty.createEvent = function( eventName ) {
var event;
if ( typeof window.Event === 'function' ) {
event = new Event( eventName );
} else {
event = document.createEvent( 'Event' );
event.initEvent( eventName, true, false );
}
return event;
};
// matches "polyfill"
// https://developer.mozilla.org/es/docs/Web/API/Element/matches
if ( ! Element.prototype.matches ) {
Element.prototype.matches =
Element.prototype.matchesSelector ||
Element.prototype.mozMatchesSelector ||
Element.prototype.msMatchesSelector ||
Element.prototype.oMatchesSelector ||
Element.prototype.webkitMatchesSelector ||
function( s ) {
var matches = ( this.document || this.ownerDocument ).querySelectorAll( s ),
i = matches.length;
while ( --i >= 0 && matches.item( i ) !== this ) {}
return i > -1;
};
}
// Add a class to the body for when touch is enabled for browsers that don't support media queries
// for interaction media features. Adapted from <https://codepen.io/Ferie/pen/vQOMmO>
( function() {
var matchMedia = function() {
// Include the 'heartz' as a way to have a non matching MQ to help terminate the join. See <https://git.io/vznFH>.
var prefixes = [ '-webkit-', '-moz-', '-o-', '-ms-' ];
var query = [ '(', prefixes.join( 'touch-enabled),(' ), 'heartz', ')' ].join( '' );
return window.matchMedia && window.matchMedia( query ).matches;
};
if ( ( 'ontouchstart' in window ) || ( window.DocumentTouch && document instanceof window.DocumentTouch ) || matchMedia() ) {
document.body.classList.add( 'touch-enabled' );
}
}() );
/* -----------------------------------------------------------------------------------------------
Cover Modals
--------------------------------------------------------------------------------------------------- */
twentytwenty.coverModals = {
init: function() {
if ( document.querySelector( '.cover-modal' ) ) {
// Handle cover modals when they're toggled
this.onToggle();
// When toggled, untoggle if visitor clicks on the wrapping element of the modal
this.outsideUntoggle();
// Close on escape key press
this.closeOnEscape();
// Hide and show modals before and after their animations have played out
this.hideAndShowModals();
}
},
// Handle cover modals when they're toggled
onToggle: function() {
document.querySelectorAll( '.cover-modal' ).forEach( function( element ) {
element.addEventListener( 'toggled', function( event ) {
var modal = event.target,
body = document.body;
if ( modal.classList.contains( 'active' ) ) {
body.classList.add( 'showing-modal' );
} else {
body.classList.remove( 'showing-modal' );
body.classList.add( 'hiding-modal' );
// Remove the hiding class after a delay, when animations have been run
setTimeout( function() {
body.classList.remove( 'hiding-modal' );
}, 500 );
}
} );
} );
},
// Close modal on outside click
outsideUntoggle: function() {
document.addEventListener( 'click', function( event ) {
var target = event.target;
var modal = document.querySelector( '.cover-modal.active' );
if ( target === modal ) {
this.untoggleModal( target );
}
}.bind( this ) );
},
// Close modal on escape key press
closeOnEscape: function() {
document.addEventListener( 'keydown', function( event ) {
if ( event.keyCode === 27 ) {
event.preventDefault();
document.querySelectorAll( '.cover-modal.active' ).forEach( function( element ) {
this.untoggleModal( element );
}.bind( this ) );
}
}.bind( this ) );
},
// Hide and show modals before and after their animations have played out
hideAndShowModals: function() {
var _doc = document,
_win = window,
modals = _doc.querySelectorAll( '.cover-modal' ),
htmlStyle = _doc.documentElement.style,
adminBar = _doc.querySelector( '#wpadminbar' );
function getAdminBarHeight( negativeValue ) {
var height,
currentScroll = _win.pageYOffset;
if ( adminBar ) {
height = currentScroll + adminBar.getBoundingClientRect().height;
return negativeValue ? -height : height;
}
return currentScroll === 0 ? 0 : -currentScroll;
}
function htmlStyles() {
var overflow = _win.innerHeight > _doc.documentElement.getBoundingClientRect().height;
return {
'overflow-y': overflow ? 'hidden' : 'scroll',
position: 'fixed',
width: '100%',
top: getAdminBarHeight( true ) + 'px',
left: 0
};
}
// Show the modal
modals.forEach( function( modal ) {
modal.addEventListener( 'toggle-target-before-inactive', function( event ) {
var styles = htmlStyles(),
offsetY = _win.pageYOffset,
paddingTop = ( Math.abs( getAdminBarHeight() ) - offsetY ) + 'px',
mQuery = _win.matchMedia( '(max-width: 600px)' );
if ( event.target !== modal ) {
return;
}
Object.keys( styles ).forEach( function( styleKey ) {
htmlStyle.setProperty( styleKey, styles[ styleKey ] );
} );
_win.twentytwenty.scrolled = parseInt( styles.top, 10 );
if ( adminBar ) {
_doc.body.style.setProperty( 'padding-top', paddingTop );
if ( mQuery.matches ) {
if ( offsetY >= getAdminBarHeight() ) {
modal.style.setProperty( 'top', 0 );
} else {
modal.style.setProperty( 'top', ( getAdminBarHeight() - offsetY ) + 'px' );
}
}
}
modal.classList.add( 'show-modal' );
} );
// Hide the modal after a delay, so animations have time to play out
modal.addEventListener( 'toggle-target-after-inactive', function( event ) {
if ( event.target !== modal ) {
return;
}
setTimeout( function() {
var clickedEl = twentytwenty.toggles.clickedEl;
modal.classList.remove( 'show-modal' );
Object.keys( htmlStyles() ).forEach( function( styleKey ) {
htmlStyle.removeProperty( styleKey );
} );
if ( adminBar ) {
_doc.body.style.removeProperty( 'padding-top' );
modal.style.removeProperty( 'top' );
}
if ( clickedEl !== false ) {
clickedEl.focus();
clickedEl = false;
}
_win.scrollTo( 0, Math.abs( _win.twentytwenty.scrolled + getAdminBarHeight() ) );
_win.twentytwenty.scrolled = 0;
}, 500 );
} );
} );
},
// Untoggle a modal
untoggleModal: function( modal ) {
var modalTargetClass,
modalToggle = false;
// If the modal has specified the string (ID or class) used by toggles to target it, untoggle the toggles with that target string
// The modal-target-string must match the string toggles use to target the modal
if ( modal.dataset.modalTargetString ) {
modalTargetClass = modal.dataset.modalTargetString;
modalToggle = document.querySelector( '*[data-toggle-target="' + modalTargetClass + '"]' );
}
// If a modal toggle exists, trigger it so all of the toggle options are included
if ( modalToggle ) {
modalToggle.click();
// If one doesn't exist, just hide the modal
} else {
modal.classList.remove( 'active' );
}
}
}; // twentytwenty.coverModals
/* -----------------------------------------------------------------------------------------------
Intrinsic Ratio Embeds
--------------------------------------------------------------------------------------------------- */
twentytwenty.intrinsicRatioVideos = {
init: function() {
this.makeFit();
window.addEventListener( 'resize', function() {
this.makeFit();
}.bind( this ) );
},
makeFit: function() {
document.querySelectorAll( 'iframe, object, video' ).forEach( function( video ) {
var ratio, iTargetWidth,
container = video.parentNode;
// Skip videos we want to ignore
if ( video.classList.contains( 'intrinsic-ignore' ) || video.parentNode.classList.contains( 'intrinsic-ignore' ) ) {
return true;
}
if ( ! video.dataset.origwidth ) {
// Get the video element proportions
video.setAttribute( 'data-origwidth', video.width );
video.setAttribute( 'data-origheight', video.height );
}
iTargetWidth = container.offsetWidth;
// Get ratio from proportions
ratio = iTargetWidth / video.dataset.origwidth;
// Scale based on ratio, thus retaining proportions
video.style.width = iTargetWidth + 'px';
video.style.height = ( video.dataset.origheight * ratio ) + 'px';
} );
}
}; // twentytwenty.instrinsicRatioVideos
/* -----------------------------------------------------------------------------------------------
Smooth Scroll
--------------------------------------------------------------------------------------------------- */
twentytwenty.smoothScroll = {
init: function() {
// Scroll to anchor
this.scrollToAnchor();
// Scroll to element
this.scrollToElement();
},
// Scroll to anchor
scrollToAnchor: function() {
var anchorElements = document.querySelectorAll( 'a[href*="#"]' );
var anchorElementsList = Array.prototype.slice.call( anchorElements );
anchorElementsList.filter( function( element ) {
if ( element.href === '#' || element.href === '#0' || element.id === 'cancel-comment-reply-link' || element.classList.contains( 'do-not-scroll' ) || element.classList.contains( 'skip-link' ) ) {
return false;
}
return true;
} ).forEach( function( element ) {
element.addEventListener( 'click', function( event ) {
var target, scrollOffset, originalOffset, adminBar, scrollSpeed, additionalOffset;
// On-page links
if ( window.location.hostname === event.target.hostname ) {
// Figure out element to scroll to
target = window.location.hash !== '' && document.querySelector( window.location.hash );
target = target ? target : event.target.hash !== '' && document.querySelector( event.target.hash );
// Does a scroll target exist?
if ( target ) {
// Only prevent default if animation is actually gonna happen
event.preventDefault();
// Get options
additionalOffset = event.target.dataset.additionalOffset;
scrollSpeed = event.target.dataset.scrollSpeed ? event.target.dataset.scrollSpeed : 500;
// Determine offset
adminBar = document.querySelector( '#wpadminbar' );
originalOffset = target.getBoundingClientRect().top + window.pageYOffset;
scrollOffset = additionalOffset ? originalOffset + additionalOffset : originalOffset;
if ( adminBar && event.target.className === 'to-the-top' ) {
scrollOffset = scrollOffset - adminBar.getBoundingClientRect().height;
}
twentytwentyScrollTo( scrollOffset, null, scrollSpeed );
window.location.hash = event.target.hash.slice( 1 );
}
}
} );
} );
},
// Scroll to element
scrollToElement: function() {
var scrollToElement = document.querySelector( '*[data-scroll-to]' );
if ( scrollToElement ) {
scrollToElement.addEventListener( 'click', function( event ) {
var originalOffset, additionalOffset, scrollOffset, scrollSpeed,
// Figure out element to scroll to
target = event.target.dataset.twentytwentyScrollTo;
// Make sure said element exists
if ( target ) {
event.preventDefault();
// Get options
additionalOffset = event.target.dataset.additionalOffset;
scrollSpeed = event.target.dataset.scrollSpeed ? event.target.dataset.scrollSpeed : 500;
// Determine offset
originalOffset = target.getBoundingClientRect().top + window.pageYOffset;
scrollOffset = additionalOffset ? originalOffset + additionalOffset : originalOffset;
twentytwentyScrollTo( scrollOffset, null, scrollSpeed );
}
} );
}
}
}; // twentytwenty.smoothScroll
/* -----------------------------------------------------------------------------------------------
Modal Menu
--------------------------------------------------------------------------------------------------- */
twentytwenty.modalMenu = {
init: function() {
// If the current menu item is in a sub level, expand all the levels higher up on load
this.expandLevel();
this.keepFocusInModal();
},
expandLevel: function() {
var modalMenus = document.querySelectorAll( '.modal-menu' );
modalMenus.forEach( function( modalMenu ) {
var activeMenuItem = modalMenu.querySelector( '.current-menu-item' );
if ( activeMenuItem ) {
twentytwentyFindParents( activeMenuItem, 'li' ).forEach( function( element ) {
var subMenuToggle = element.querySelector( '.sub-menu-toggle' );
if ( subMenuToggle ) {
twentytwenty.toggles.performToggle( subMenuToggle, true );
}
} );
}
} );
},
keepFocusInModal: function() {
var _doc = document;
_doc.addEventListener( 'keydown', function( event ) {
var toggleTarget, modal, selectors, elements, menuType, bottomMenu, activeEl, lastEl, firstEl, tabKey, shiftKey,
clickedEl = twentytwenty.toggles.clickedEl;
if ( clickedEl && _doc.body.classList.contains( 'showing-modal' ) ) {
toggleTarget = clickedEl.dataset.toggleTarget;
selectors = 'input, a, button';
modal = _doc.querySelector( toggleTarget );
elements = modal.querySelectorAll( selectors );
elements = Array.prototype.slice.call( elements );
if ( '.menu-modal' === toggleTarget ) {
menuType = window.matchMedia( '(min-width: 1000px)' ).matches;
menuType = menuType ? '.expanded-menu' : '.mobile-menu';
elements = elements.filter( function( element ) {
return null !== element.closest( menuType ) && null !== element.offsetParent;
} );
elements.unshift( _doc.querySelector( '.close-nav-toggle' ) );
bottomMenu = _doc.querySelector( '.menu-bottom > nav' );
if ( bottomMenu ) {
bottomMenu.querySelectorAll( selectors ).forEach( function( element ) {
elements.push( element );
} );
}
}
lastEl = elements[ elements.length - 1 ];
firstEl = elements[0];
activeEl = _doc.activeElement;
tabKey = event.keyCode === 9;
shiftKey = event.shiftKey;
if ( ! shiftKey && tabKey && lastEl === activeEl ) {
event.preventDefault();
firstEl.focus();
}
if ( shiftKey && tabKey && firstEl === activeEl ) {
event.preventDefault();
lastEl.focus();
}
}
} );
}
}; // twentytwenty.modalMenu
/* -----------------------------------------------------------------------------------------------
Primary Menu
--------------------------------------------------------------------------------------------------- */
twentytwenty.primaryMenu = {
init: function() {
this.focusMenuWithChildren();
},
// The focusMenuWithChildren() function implements Keyboard Navigation in the Primary Menu
// by adding the '.focus' class to all 'li.menu-item-has-children' when the focus is on the 'a' element.
focusMenuWithChildren: function() {
// Get all the link elements within the primary menu.
var links, i, len,
menu = document.querySelector( '.primary-menu-wrapper' );
if ( ! menu ) {
return false;
}
links = menu.getElementsByTagName( 'a' );
// Each time a menu link is focused or blurred, toggle focus.
for ( i = 0, len = links.length; i < len; i++ ) {
links[i].addEventListener( 'focus', toggleFocus, true );
links[i].addEventListener( 'blur', toggleFocus, true );
}
//Sets or removes the .focus class on an element.
function toggleFocus() {
var self = this;
// Move up through the ancestors of the current link until we hit .primary-menu.
while ( -1 === self.className.indexOf( 'primary-menu' ) ) {
// On li elements toggle the class .focus.
if ( 'li' === self.tagName.toLowerCase() ) {
if ( -1 !== self.className.indexOf( 'focus' ) ) {
self.className = self.className.replace( ' focus', '' );
} else {
self.className += ' focus';
}
}
self = self.parentElement;
}
}
}
}; // twentytwenty.primaryMenu
/* -----------------------------------------------------------------------------------------------
Toggles
--------------------------------------------------------------------------------------------------- */
twentytwenty.toggles = {
clickedEl: false,
init: function() {
// Do the toggle
this.toggle();
// Check for toggle/untoggle on resize
this.resizeCheck();
// Check for untoggle on escape key press
this.untoggleOnEscapeKeyPress();
},
performToggle: function( element, instantly ) {
var target, timeOutTime, classToToggle,
self = this,
_doc = document,
// Get our targets
toggle = element,
targetString = toggle.dataset.toggleTarget,
activeClass = 'active';
// Elements to focus after modals are closed
if ( ! _doc.querySelectorAll( '.show-modal' ).length ) {
self.clickedEl = _doc.activeElement;
}
if ( targetString === 'next' ) {
target = toggle.nextSibling;
} else {
target = _doc.querySelector( targetString );
}
// Trigger events on the toggle targets before they are toggled
if ( target.classList.contains( activeClass ) ) {
target.dispatchEvent( twentytwenty.createEvent( 'toggle-target-before-active' ) );
} else {
target.dispatchEvent( twentytwenty.createEvent( 'toggle-target-before-inactive' ) );
}
// Get the class to toggle, if specified
classToToggle = toggle.dataset.classToToggle ? toggle.dataset.classToToggle : activeClass;
// For cover modals, set a short timeout duration so the class animations have time to play out
timeOutTime = 0;
if ( target.classList.contains( 'cover-modal' ) ) {
timeOutTime = 10;
}
setTimeout( function() {
var focusElement,
subMenued = target.classList.contains( 'sub-menu' ),
newTarget = subMenued ? toggle.closest( '.menu-item' ).querySelector( '.sub-menu' ) : target,
duration = toggle.dataset.toggleDuration;
// Toggle the target of the clicked toggle
if ( toggle.dataset.toggleType === 'slidetoggle' && ! instantly && duration !== '0' ) {
twentytwentyMenuToggle( newTarget, duration );
} else {
newTarget.classList.toggle( classToToggle );
}
// If the toggle target is 'next', only give the clicked toggle the active class
if ( targetString === 'next' ) {
toggle.classList.toggle( activeClass );
} else if ( target.classList.contains( 'sub-menu' ) ) {
toggle.classList.toggle( activeClass );
} else {
// If not, toggle all toggles with this toggle target
_doc.querySelector( '*[data-toggle-target="' + targetString + '"]' ).classList.toggle( activeClass );
}
// Toggle aria-expanded on the toggle
twentytwentyToggleAttribute( toggle, 'aria-expanded', 'true', 'false' );
if ( self.clickedEl && -1 !== toggle.getAttribute( 'class' ).indexOf( 'close-' ) ) {
twentytwentyToggleAttribute( self.clickedEl, 'aria-expanded', 'true', 'false' );
}
// Toggle body class
if ( toggle.dataset.toggleBodyClass ) {
_doc.body.classList.toggle( toggle.dataset.toggleBodyClass );
}
// Check whether to set focus
if ( toggle.dataset.setFocus ) {
focusElement = _doc.querySelector( toggle.dataset.setFocus );
if ( focusElement ) {
if ( target.classList.contains( activeClass ) ) {
focusElement.focus();
} else {
focusElement.blur();
}
}
}
// Trigger the toggled event on the toggle target
target.dispatchEvent( twentytwenty.createEvent( 'toggled' ) );
// Trigger events on the toggle targets after they are toggled
if ( target.classList.contains( activeClass ) ) {
target.dispatchEvent( twentytwenty.createEvent( 'toggle-target-after-active' ) );
} else {
target.dispatchEvent( twentytwenty.createEvent( 'toggle-target-after-inactive' ) );
}
}, timeOutTime );
},
// Do the toggle
toggle: function() {
var self = this;
document.querySelectorAll( '*[data-toggle-target]' ).forEach( function( element ) {
element.addEventListener( 'click', function( event ) {
event.preventDefault();
self.performToggle( element );
} );
} );
},
// Check for toggle/untoggle on screen resize
resizeCheck: function() {
if ( document.querySelectorAll( '*[data-untoggle-above], *[data-untoggle-below], *[data-toggle-above], *[data-toggle-below]' ).length ) {
window.addEventListener( 'resize', function() {
var winWidth = window.innerWidth,
toggles = document.querySelectorAll( '.toggle' );
toggles.forEach( function( toggle ) {
var unToggleAbove = toggle.dataset.untoggleAbove,
unToggleBelow = toggle.dataset.untoggleBelow,
toggleAbove = toggle.dataset.toggleAbove,
toggleBelow = toggle.dataset.toggleBelow;
// If no width comparison is set, continue
if ( ! unToggleAbove && ! unToggleBelow && ! toggleAbove && ! toggleBelow ) {
return;
}
// If the toggle width comparison is true, toggle the toggle
if (
( ( ( unToggleAbove && winWidth > unToggleAbove ) ||
( unToggleBelow && winWidth < unToggleBelow ) ) &&
toggle.classList.contains( 'active' ) ) ||
( ( ( toggleAbove && winWidth > toggleAbove ) ||
( toggleBelow && winWidth < toggleBelow ) ) &&
! toggle.classList.contains( 'active' ) )
) {
toggle.click();
}
} );
} );
}
},
// Close toggle on escape key press
untoggleOnEscapeKeyPress: function() {
document.addEventListener( 'keyup', function( event ) {
if ( event.key === 'Escape' ) {
document.querySelectorAll( '*[data-untoggle-on-escape].active' ).forEach( function( element ) {
if ( element.classList.contains( 'active' ) ) {
element.click();
}
} );
}
} );
}
}; // twentytwenty.toggles
/**
* Is the DOM ready
*
* this implementation is coming from https://gomakethings.com/a-native-javascript-equivalent-of-jquerys-ready-method/
*
* @param {Function} fn Callback function to run.
*/
function twentytwentyDomReady( fn ) {
if ( typeof fn !== 'function' ) {
return;
}
if ( document.readyState === 'interactive' || document.readyState === 'complete' ) {
return fn();
}
document.addEventListener( 'DOMContentLoaded', fn, false );
}
twentytwentyDomReady( function() {
twentytwenty.toggles.init(); // Handle toggles
twentytwenty.coverModals.init(); // Handle cover modals
twentytwenty.intrinsicRatioVideos.init(); // Retain aspect ratio of videos on window resize
twentytwenty.smoothScroll.init(); // Smooth scroll to anchor link or a specific element
twentytwenty.modalMenu.init(); // Modal Menu
twentytwenty.primaryMenu.init(); // Primary Menu
} );
/* -----------------------------------------------------------------------------------------------
Helper functions
--------------------------------------------------------------------------------------------------- */
/* Toggle an attribute ----------------------- */
function twentytwentyToggleAttribute( element, attribute, trueVal, falseVal ) {
if ( trueVal === undefined ) {
trueVal = true;
}
if ( falseVal === undefined ) {
falseVal = false;
}
if ( element.getAttribute( attribute ) !== trueVal ) {
element.setAttribute( attribute, trueVal );
} else {
element.setAttribute( attribute, falseVal );
}
}
/**
* Toggle a menu item on or off.
*
* @param {HTMLElement} target
* @param {number} duration
*/
function twentytwentyMenuToggle( target, duration ) {
var initialParentHeight, finalParentHeight, menu, menuItems, transitionListener,
initialPositions = [],
finalPositions = [];
if ( ! target ) {
return;
}
menu = target.closest( '.menu-wrapper' );
// Step 1: look at the initial positions of every menu item.
menuItems = menu.querySelectorAll( '.menu-item' );
menuItems.forEach( function( menuItem, index ) {
initialPositions[ index ] = { x: menuItem.offsetLeft, y: menuItem.offsetTop };
} );
initialParentHeight = target.parentElement.offsetHeight;
target.classList.add( 'toggling-target' );
// Step 2: toggle target menu item and look at the final positions of every menu item.
target.classList.toggle( 'active' );
menuItems.forEach( function( menuItem, index ) {
finalPositions[ index ] = { x: menuItem.offsetLeft, y: menuItem.offsetTop };
} );
finalParentHeight = target.parentElement.offsetHeight;
// Step 3: close target menu item again.
// The whole process happens without giving the browser a chance to render, so it's invisible.
target.classList.toggle( 'active' );
// Step 4: prepare animation.
// Position all the items with absolute offsets, at the same starting position.
// Shouldn't result in any visual changes if done right.
menu.classList.add( 'is-toggling' );
target.classList.toggle( 'active' );
menuItems.forEach( function( menuItem, index ) {
var initialPosition = initialPositions[ index ];
if ( initialPosition.y === 0 && menuItem.parentElement === target ) {
initialPosition.y = initialParentHeight;
}
menuItem.style.transform = 'translate(' + initialPosition.x + 'px, ' + initialPosition.y + 'px)';
} );
// The double rAF is unfortunately needed, since we're toggling CSS classes, and
// the only way to ensure layout completion here across browsers is to wait twice.
// This just delays the start of the animation by 2 frames and is thus not an issue.
requestAnimationFrame( function() {
requestAnimationFrame( function() {
// Step 5: start animation by moving everything to final position.
// All the layout work has already happened, while we were preparing for the animation.
// The animation now runs entirely in CSS, using cheap CSS properties (opacity and transform)
// that don't trigger the layout or paint stages.
menu.classList.add( 'is-animating' );
menuItems.forEach( function( menuItem, index ) {
var finalPosition = finalPositions[ index ];
if ( finalPosition.y === 0 && menuItem.parentElement === target ) {
finalPosition.y = finalParentHeight;
}
if ( duration !== undefined ) {
menuItem.style.transitionDuration = duration + 'ms';
}
menuItem.style.transform = 'translate(' + finalPosition.x + 'px, ' + finalPosition.y + 'px)';
} );
if ( duration !== undefined ) {
target.style.transitionDuration = duration + 'ms';
}
} );
// Step 6: finish toggling.
// Remove all transient classes when the animation ends.
transitionListener = function() {
menu.classList.remove( 'is-animating' );
menu.classList.remove( 'is-toggling' );
target.classList.remove( 'toggling-target' );
menuItems.forEach( function( menuItem ) {
menuItem.style.transform = '';
menuItem.style.transitionDuration = '';
} );
target.style.transitionDuration = '';
target.removeEventListener( 'transitionend', transitionListener );
};
target.addEventListener( 'transitionend', transitionListener );
} );
}
/**
* traverses the DOM up to find elements matching the query
*
* @param {HTMLElement} target
* @param {string} query
* @return {NodeList} parents matching query
*/
function twentytwentyFindParents( target, query ) {
var parents = [];
// recursively go up the DOM adding matches to the parents array
function traverse( item ) {
var parent = item.parentNode;
if ( parent instanceof HTMLElement ) {
if ( parent.matches( query ) ) {
parents.push( parent );
}
traverse( parent );
}
}
traverse( target );
return parents;
}
// twentytwentyEaseInOutQuad functions http://goo.gl/5HLl8
function twentytwentyEaseInOutQuad( t, b, c, d ) {
t /= d / 2;
if ( t < 1 ) {
return ( ( ( c / 2 ) * t ) * t ) + b;
}
t--;
return ( ( -c / 2 ) * ( ( t * ( t - 2 ) ) - 1 ) ) + b;
}
function twentytwentyScrollTo( to, callback, duration ) {
var start, change, increment, currentTime;
function move( amount ) {
document.documentElement.scrollTop = amount;
document.body.parentNode.scrollTop = amount;
document.body.scrollTop = amount;
}
start = document.documentElement.scrollTop || document.body.parentNode.scrollTop || document.body.scrollTop;
change = to - start;
increment = 20;
currentTime = 0;
duration = ( typeof ( duration ) === 'undefined' ) ? 500 : duration;
function animateScroll() {
var val;
// increment the time
currentTime += increment;
// find the value with the quadratic in-out twentytwentyEaseInOutQuad function
val = twentytwentyEaseInOutQuad( currentTime, start, change, duration );
// move the document.body
move( val );
// do the animation unless its over
if ( currentTime < duration ) {
window.requestAnimationFrame( animateScroll );
} else if ( callback && typeof ( callback ) === 'function' ) {
// the animation is done so lets callback
callback();
}
}
animateScroll();
}