mediawiki-extensions-Tabber.../modules/ext.tabberNeue.js
alistair3149 1f4436843f
feat: improve loading behavior before module is added
* Add skeleton screen to avoid layout shift
* Hide other sections before the module is loaded to avoid layout shift
* Add noscript message
* Header container is now saved in parser instead of being generated.
If you have any issues with the script, try clearing out the parser cache
or do an empty edit.
2022-05-06 17:53:52 -04:00

378 lines
11 KiB
JavaScript

/**
* Initialize Tabber
*
* @param {HTMLElement} tabber
* @param {number} count
*/
function initTabber( tabber, count ) {
var tabPanels = tabber.querySelectorAll( ':scope > .tabber__section > .tabber__panel' );
var config = require( './config.json' ),
header = tabber.querySelector( '.tabber__header' ),
tabList = document.createElement( 'nav' ),
prevButton = document.createElement( 'div' ),
nextButton = document.createElement( 'div' );
var buildTabs = function () {
var fragment = new DocumentFragment();
Array.prototype.forEach.call( tabPanels, function ( tabPanel ) {
var hash = mw.util.escapeIdForAttribute( tabPanel.title ) + '-' + count,
tab = document.createElement( 'a' );
tabPanel.setAttribute( 'id', hash );
tabPanel.setAttribute( 'role', 'tabpanel' );
tabPanel.setAttribute( 'aria-labelledby', 'tab-' + hash );
tabPanel.setAttribute( 'aria-hidden', true );
tab.innerText = tabPanel.title;
tab.classList.add( 'tabber__tab' );
tab.setAttribute( 'title', tabPanel.title );
tab.setAttribute( 'role', 'tab' );
tab.setAttribute( 'href', '#' + hash );
tab.setAttribute( 'id', 'tab-' + hash );
tab.setAttribute( 'aria-selected', false );
tab.setAttribute( 'aria-controls', hash );
fragment.append( tab );
} );
tabList.append( fragment );
tabList.classList.add( 'tabber__tabs' );
tabList.setAttribute( 'role', 'tablist' );
prevButton.classList.add( 'tabber__header__prev' );
nextButton.classList.add( 'tabber__header__next' );
header.append( prevButton, tabList, nextButton );
};
var updateSectionHeight = function ( section, activePanel ) {
var height = activePanel.offsetHeight;
if ( height === 0 ) {
// Sometimes the tab is hidden by one of its parent elements
// and you can only get the actual height by cloning the element
var clone = activePanel.cloneNode( true );
// Hide the cloned element
clone.style.cssText = 'position:absolute;visibility:hidden;';
// Add cloned element to body
document.body.appendChild( clone );
// Measure the height of the clone
height = clone.clientHeight;
// Remove the cloned element
clone.parentNode.removeChild( clone );
}
section.style.height = String( height ) + 'px';
// Scroll to tab
section.scrollLeft = activePanel.offsetLeft;
};
var onElementResize = function ( entries ) {
if ( entries && entries.length > 0 ) {
var targetPanel = entries[ 0 ].target;
var section = targetPanel.parentNode;
updateSectionHeight( section, targetPanel );
}
};
var resizeObserver = null;
if ( window.ResizeObserver ) {
resizeObserver = new ResizeObserver( mw.util.debounce( 250, onElementResize ) );
}
buildTabs();
tabber.prepend( header );
// Initalize previous and next buttons
var initButtons = function () {
var PREVCLASS = 'tabber__header--prev-visible',
NEXTCLASS = 'tabber__header--next-visible';
/* eslint-disable mediawiki/class-doc */
var scrollTabs = function ( offset ) {
var scrollLeft = tabList.scrollLeft + offset;
// Scroll to the start
if ( scrollLeft <= 0 ) {
tabList.scrollLeft = 0;
} else {
tabList.scrollLeft = scrollLeft;
}
};
var updateButtons = function () {
var scrollLeft = tabList.scrollLeft;
// Scroll to the start
if ( scrollLeft <= 0 ) {
header.classList.remove( PREVCLASS );
header.classList.add( NEXTCLASS );
} else {
// Scroll to the end
if ( scrollLeft + tabList.offsetWidth >= tabList.scrollWidth ) {
header.classList.remove( NEXTCLASS );
header.classList.add( PREVCLASS );
} else {
header.classList.add( NEXTCLASS );
header.classList.add( PREVCLASS );
}
}
};
var setupButtons = function () {
var isScrollable = ( tabList.scrollWidth > header.offsetWidth );
if ( isScrollable ) {
var scrollOffset = header.offsetWidth / 2;
// Just to add the right classes
updateButtons();
// Button only shows on pointer devices
if ( matchMedia( '(hover: hover)' ).matches ) {
prevButton.addEventListener( 'click', function () {
scrollTabs( -scrollOffset );
}, false );
nextButton.addEventListener( 'click', function () {
scrollTabs( scrollOffset );
}, false );
}
} else {
header.classList.remove( NEXTCLASS );
header.classList.remove( PREVCLASS );
}
};
/* eslint-enable mediawiki/class-doc */
setupButtons();
// Listen for scroll event on header
// Also triggered by side-scrolling using other means other than the buttons
tabList.addEventListener( 'scroll', function () {
updateButtons();
} );
// Listen for element resize
if ( window.ResizeObserver ) {
var tabListResizeObserver = new ResizeObserver( mw.util.debounce( 250, setupButtons ) );
tabListResizeObserver.observe( tabList );
}
};
// NOTE: Are there better ways to scope them?
var xhr = new XMLHttpRequest();
var currentRequest = null, nextRequest = null;
/**
* Loads page contents into tab
*
* @param {HTMLElement} targetPanel
* @param {string} url
*/
function loadPage( targetPanel, url ) {
var requestData = {
url: url,
targetPanel: targetPanel
};
if ( currentRequest ) {
if ( currentRequest.url !== requestData.url ) {
nextRequest = requestData;
}
// busy
return;
}
xhr.open( 'GET', url );
currentRequest = requestData;
xhr.send( null );
}
/**
* Show panel based on target hash
*
* @param {string} targetHash
* @param {boolean} allowRemoteLoad
*/
function showPanel( targetHash, allowRemoteLoad ) {
var ACTIVETABCLASS = 'tabber__tab--active',
ACTIVEPANELCLASS = 'tabber__panel--active',
targetPanel = document.getElementById( targetHash ),
targetTab = document.getElementById( 'tab-' + targetHash ),
section = targetPanel.parentNode,
activePanel = section.querySelector( ':scope > .' + ACTIVEPANELCLASS ),
parentPanel, parentSection;
var loadTransclusion = function () {
var loading = document.createElement( 'div' ),
indicator = document.createElement( 'div' );
targetPanel.setAttribute( 'aria-live', 'polite' );
targetPanel.setAttribute( 'aria-busy', 'true' );
loading.setAttribute( 'class', 'tabber__transclusion--loading' );
indicator.setAttribute( 'class', 'tabber__loading-indicator' );
loading.appendChild( indicator );
targetPanel.textContent = '';
targetPanel.appendChild( loading );
loadPage( targetPanel, targetPanel.dataset.tabberLoadUrl );
};
/* eslint-disable mediawiki/class-doc */
if ( activePanel ) {
// Just to be safe since there can be multiple active classes
// even if there shouldn't be
var activeTabs = tabList.querySelectorAll( '.' + ACTIVETABCLASS );
if ( activeTabs.length > 0 ) {
Array.prototype.forEach.call( activeTabs, function ( activeTab ) {
activeTab.classList.remove( ACTIVETABCLASS );
activeTab.setAttribute( 'aria-selected', false );
} );
}
if ( resizeObserver ) {
resizeObserver.unobserve( activePanel );
}
activePanel.classList.remove( ACTIVEPANELCLASS );
activePanel.setAttribute( 'aria-hidden', true );
}
// Add active class to the tab
targetTab.classList.add( ACTIVETABCLASS );
targetTab.setAttribute( 'aria-selected', true );
targetPanel.classList.add( ACTIVEPANELCLASS );
targetPanel.setAttribute( 'aria-hidden', false );
// Lazyload transclusion if needed
if ( allowRemoteLoad &&
targetPanel.dataset.tabberPendingLoad &&
targetPanel.dataset.tabberLoadUrl
) {
loadTransclusion();
}
updateSectionHeight( section, targetPanel );
// If we're inside another tab, trigger its logic to recalc its height
parentSection = section;
// ResizeObserver should take care of the recursivity already
/* eslint-disable-next-line no-unmodified-loop-condition */
while ( !resizeObserver ) {
parentPanel = parentSection.closest( '.' + ACTIVEPANELCLASS );
if ( !parentPanel ) {
break;
}
parentSection = parentPanel.parentNode;
updateSectionHeight( parentSection, parentPanel );
}
if ( resizeObserver ) {
resizeObserver.observe( targetPanel );
}
/* eslint-enable mediawiki/class-doc */
}
/**
* Event handler for XMLHttpRequest where ends loading
*/
function onLoadEndPage() {
var targetPanel = currentRequest.targetPanel;
if ( xhr.status !== 200 ) {
var err = document.createElement( 'div' ),
errMsg = mw.message( 'error' ).text() + ': HTTP ' + xhr.status;
err.setAttribute( 'class', 'tabber__transclusion--error error' );
err.appendChild( document.createTextNode( errMsg ) );
targetPanel.textContent = '';
targetPanel.appendChild( err );
} else {
var result = JSON.parse( xhr.responseText );
targetPanel.innerHTML = result.parse.text;
// wikipage.content hook requires a jQuery object
/* eslint-disable-next-line no-undef */
mw.hook( 'wikipage.content' ).fire( $( targetPanel ) );
delete targetPanel.dataset.tabberPendingLoad;
delete targetPanel.dataset.tabberLoadUrl;
targetPanel.setAttribute( 'aria-busy', 'false' );
}
var ACTIVEPANELCLASS = 'tabber__panel--active',
targetHash = targetPanel.getAttribute( 'id' ),
section = targetPanel.parentNode,
activePanel = section.querySelector( ':scope > .' + ACTIVEPANELCLASS );
if ( nextRequest ) {
currentRequest = nextRequest;
nextRequest = null;
xhr.open( 'GET', currentRequest.url );
xhr.send( null );
} else {
currentRequest = null;
}
if ( activePanel ) {
// Refresh height
showPanel( targetHash, false );
}
}
xhr.timeout = 20000;
xhr.addEventListener( 'loadend', onLoadEndPage );
/**
* Retrieve target hash and trigger show panel
* If no targetHash is invalid, use the first panel
*
* @param {HTMLElement} tabber
*/
function switchTab() {
var targetHash = new mw.Uri( location.href ).fragment;
// Switch to the first tab if no targetHash or no tab is detected
// TODO: Remove the polyfill with CSS.escape when we are dropping IE support
if ( !targetHash || !tabList.querySelector( '#tab-' + targetHash.replace( /[^a-zA-Z0-9-_]/g, '\\$&' ) ) ) {
targetHash = tabList.firstElementChild.getAttribute( 'id' ).substring( 4 );
}
showPanel( targetHash );
}
switchTab();
initButtons();
// window.addEventListener( 'hashchange', switchTab, false );
// Respond to clicks on the nav tabs
Array.prototype.forEach.call( tabList.children, function ( tab ) {
tab.addEventListener( 'click', function ( event ) {
var targetHash = tab.getAttribute( 'href' ).substring( 1 );
event.preventDefault();
if ( !config || config.updateLocationOnTabChange ) {
// Add hash to the end of the URL
history.replaceState( null, null, '#' + targetHash );
}
showPanel( targetHash, true );
} );
} );
tabber.classList.add( 'tabber--live' );
}
function main() {
var tabbers = document.querySelectorAll( '.tabber:not( .tabber--live )' ),
style = document.getElementById( 'tabber-style' );
if ( tabbers ) {
var count = 0;
mw.loader.load( 'ext.tabberNeue.icons' );
Array.prototype.forEach.call( tabbers, function ( tabber ) {
initTabber( tabber, count );
count++;
} );
// Remove critical render styles after done
// IE compatiblity
style.parentNode.removeChild( style );
}
}
main();