W3C Accessibility Working Group は、開発者が Web パターンやウィジェットにアクセシビリティ セマンティクスを組み込むのを支援するために、Web Accessibility Initiative を開始しました。ウィジェットは、アクセシブルなエクスペリエンスを作成する際に重視されます。マテリアル デザイン、Fluent UI、ヒューマン インターフェイス UI などのデザイン システムは、ブラウザ プラットフォーム上の Web コンポーネントを使用して構築されるウィジェット ベースのデザイン システムであり、ネイティブ プラットフォームに変換される場合は Web アクセシビリティ ガイドラインに厳密に従います。これらのセマンティクスを使用すると、Web サイトのアクセシビリティが向上するだけでなく、開発速度も向上します。
イメージ カルーセルやアラート ダイアログの構築に問題があり、NPM からパッケージをダウンロードする必要があったことがありますか?もうない。 Web アクセシビリティ イニシアチブはあなたをサポートします。 CodePen で表示できるサンプル ウィジェットとパターンが含まれています。サンプルをプロジェクトにダウンロードし、変更すれば完了です。 Image Carousel を構築する方法がわかり、NPM からパッケージをダウンロードしなくてもアクセスできるようになります
画像カルーセルの例:
<section> <ul> <li>CSS </li> </ul> <pre class="brush:php;toolbar:false">/* .carousel */ img.reload { padding: 0.25em; display: block-inline; position: relative; top: 6px; height: 0.9em; } .carousel { background-color: #eee; max-width: 900px; } .carousel .carousel-inner { position: relative; } .carousel .carousel-items { padding: 5px; } .carousel .carousel-items.focus { padding: 2px; border: solid 3px #005a9c; } .carousel .carousel-item { display: none; max-height: 400px; max-width: 900px; position: relative; overflow: hidden; width: 100%; } .carousel .carousel-item.active { display: block; } /* More like bootstrap, less accessible */ .carousel .carousel-item .carousel-image a img { height: 100%; width: 100%; } .carousel .carousel-item .carousel-caption a { cursor: pointer; text-decoration: underline; color: #fff; font-weight: 600; } .carousel .carousel-item .carousel-caption a, .carousel .carousel-item .carousel-caption span.contrast { display: inline-block; margin: 0; padding: 6px; background-color: rgb(0 0 0 / 65%); border-radius: 5px; border: 0 solid transparent; } .carousel-moreaccessible .carousel-items .carousel-image a { display: block; margin: 0; padding: 5px; text-decoration: none; border: none; } .carousel-moreaccessible .carousel-item .carousel-caption a { display: inline-block; margin: 0; padding: 6px; color: black; background-color: transparent; border: none; border-radius: 5px; } .carousel-moreaccessible .carousel-item .carousel-caption span.contrast, .carousel-moreaccessible .carousel-item .carousel-caption span.contrast:hover { background-color: transparent; } .carousel .carousel-item .carousel-caption a:hover, .carousel .carousel-item .carousel-caption span.contrast:hover { background-color: rgb(0 0 0 / 100%); } .carousel .carousel-item .carousel-caption a:focus { padding: 4px; border: 2px solid #fff; background-color: rgb(0 0 0 / 100%); outline: none; border-width: 2px solid #fff; color: #fff; } .carousel .carousel-item .carousel-caption p { font-size: 1em; line-height: 1.5; margin-bottom: 0; } .carousel .carousel-item .carousel-caption { position: absolute; right: 15%; bottom: 0; left: 15%; padding-top: 20px; padding-bottom: 20px; color: #fff; text-align: center; } /* Shared CSS for Pause, Previous and Next Buttons */ .carousel .controls { box-sizing: border-box; position: absolute; top: 1em; z-index: 10; display: flex; width: 100%; padding: 0.25em 1.25em 0; } .carousel .controls button { position: absolute; z-index: 10; flex: 0 0 auto; margin: 0; padding: 0; border: none; background: transparent; outline: none; } .carousel .controls button.previous { right: 70px; } .carousel .controls button.next { right: 18px; } /* SVG Controls */ .carousel .controls svg .background { stroke: black; fill: black; stroke-width: 1px; opacity: 0.6; } .carousel .controls svg .border { fill: transparent; stroke: transparent; stroke-width: 2px; } .carousel .controls svg .pause { stroke-width: 4; fill: transparent; stroke: transparent; } .carousel .controls svg .play { stroke-width: 1; fill: transparent; stroke: transparent; } .carousel .controls .pause svg .pause { fill: white; stroke: white; } .carousel .controls .play svg .play { fill: white; stroke: white; } .carousel .controls svg polygon { fill: white; stroke: white; } .carousel .controls button:focus svg .background, .carousel .controls button:hover svg .background, .carousel .controls button:hover svg .border { fill: #005a9c; stroke: #005a9c; opacity: 1; } .carousel .controls button:focus svg .border { stroke: white; } /* More accessible carousel styles, with caption and controls above/below image */ .carousel-moreaccessible { padding: 0; margin: 0; position: relative; border: #eee solid 4px; border-radius: 5px; } /* Shared CSS for Pause and Tab Controls */ .carousel-moreaccessible .controls { position: relative; top: 0; left: 0; padding: 0.25em 0.25em 0; } .carousel.carousel-moreaccessible .controls { position: static; height: 36px; } .carousel.carousel-moreaccessible .controls button.previous { right: 60px; } .carousel.carousel-moreaccessible .controls button.next { right: 6px; } .carousel-moreaccessible .carousel-items, .carousel-moreaccessible .carousel-items.focus { padding: 0; border: none; } .carousel-moreaccessible .carousel-items.focus .carousel-image a { padding: 2px; border: 3px solid #005a9c; } /* More accessible caption styling */ .carousel-moreaccessible .carousel-item { padding: 0; margin: 0; max-height: none; } .carousel-moreaccessible .carousel-item .carousel-caption { position: static; padding: 0; margin: 0; height: 60px; color: black; } .carousel-moreaccessible .carousel-item .carousel-caption p { padding: 0; margin: 0; } .carousel-moreaccessible .carousel-item .carousel-caption h3 { font-size: 1.1em; padding: 0; margin: 0; } .carousel-moreaccessible .carousel-item .carousel-caption a:hover { background-color: rgb(0 0 0 / 20%); } .carousel-moreaccessible .carousel-item .carousel-caption a:focus { padding: 4px; border: 2px solid #005a9c; background-color: transparent; color: black; outline: none; }
/* * File: carousel-prev-next.js * * Desc: Carousel widget with Previous and Next Buttons that implements ARIA Authoring Practices * */ 'use strict'; var CarouselPreviousNext = function (node, options) { // merge passed options with defaults options = Object.assign( { moreaccessible: false, paused: false, norotate: false }, options || {} ); // a prefers-reduced-motion user setting must always override autoplay var hasReducedMotion = window.matchMedia('(prefers-reduced-motion: reduce)'); if (hasReducedMotion.matches) { options.paused = true; } /* DOM properties */ this.domNode = node; this.carouselItemNodes = node.querySelectorAll('.carousel-item'); this.containerNode = node.querySelector('.carousel-items'); this.liveRegionNode = node.querySelector('.carousel-items'); this.pausePlayButtonNode = null; this.previousButtonNode = null; this.nextButtonNode = null; this.playLabel = 'Start automatic slide show'; this.pauseLabel = 'Stop automatic slide show'; /* State properties */ this.hasUserActivatedPlay = false; // set when the user activates the play/pause button this.isAutoRotationDisabled = options.norotate; // This property for disabling auto rotation this.isPlayingEnabled = !options.paused; // This property is also set in updatePlaying method this.timeInterval = 5000; // length of slide rotation in ms this.currentIndex = 0; // index of current slide this.slideTimeout = null; // save reference to setTimeout // Pause Button var elem = document.querySelector('.carousel .controls button.rotation'); if (elem) { this.pausePlayButtonNode = elem; this.pausePlayButtonNode.addEventListener( 'click', this.handlePausePlayButtonClick.bind(this) ); } // Previous Button elem = document.querySelector('.carousel .controls button.previous'); if (elem) { this.previousButtonNode = elem; this.previousButtonNode.addEventListener( 'click', this.handlePreviousButtonClick.bind(this) ); this.previousButtonNode.addEventListener( 'focus', this.handleFocusIn.bind(this) ); this.previousButtonNode.addEventListener( 'blur', this.handleFocusOut.bind(this) ); } // Next Button elem = document.querySelector('.carousel .controls button.next'); if (elem) { this.nextButtonNode = elem; this.nextButtonNode.addEventListener( 'click', this.handleNextButtonClick.bind(this) ); this.nextButtonNode.addEventListener( 'focus', this.handleFocusIn.bind(this) ); this.nextButtonNode.addEventListener( 'blur', this.handleFocusOut.bind(this) ); } // Carousel item events for (var i = 0; i < this.carouselItemNodes.length; i++) { var carouselItemNode = this.carouselItemNodes[i]; // support stopping rotation when any element receives focus in the tabpanel carouselItemNode.addEventListener('focusin', this.handleFocusIn.bind(this)); carouselItemNode.addEventListener( 'focusout', this.handleFocusOut.bind(this) ); var imageLinkNode = carouselItemNode.querySelector('.carousel-image a'); if (imageLinkNode) { imageLinkNode.addEventListener( 'focus', this.handleImageLinkFocus.bind(this) ); imageLinkNode.addEventListener( 'blur', this.handleImageLinkBlur.bind(this) ); } } // Handle hover events this.domNode.addEventListener('mouseover', this.handleMouseOver.bind(this)); this.domNode.addEventListener('mouseout', this.handleMouseOut.bind(this)); // initialize behavior based on options this.enableOrDisableAutoRotation(options.norotate); this.updatePlaying(!options.paused && !options.norotate); this.setAccessibleStyling(options.moreaccessible); this.rotateSlides(); }; /* Public function to disable/enable rotation and if false, hide pause/play button*/ CarouselPreviousNext.prototype.enableOrDisableAutoRotation = function ( disable ) { this.isAutoRotationDisabled = disable; this.pausePlayButtonNode.hidden = disable; }; /* Public function to update controls/caption styling */ CarouselPreviousNext.prototype.setAccessibleStyling = function (accessible) { if (accessible) { this.domNode.classList.add('carousel-moreaccessible'); } else { this.domNode.classList.remove('carousel-moreaccessible'); } }; CarouselPreviousNext.prototype.showCarouselItem = function (index) { this.currentIndex = index; for (var i = 0; i < this.carouselItemNodes.length; i++) { var carouselItemNode = this.carouselItemNodes[i]; if (index === i) { carouselItemNode.classList.add('active'); } else { carouselItemNode.classList.remove('active'); } } }; CarouselPreviousNext.prototype.previousCarouselItem = function () { var nextIndex = this.currentIndex - 1; if (nextIndex < 0) { nextIndex = this.carouselItemNodes.length - 1; } this.showCarouselItem(nextIndex); }; CarouselPreviousNext.prototype.nextCarouselItem = function () { var nextIndex = this.currentIndex + 1; if (nextIndex >= this.carouselItemNodes.length) { nextIndex = 0; } this.showCarouselItem(nextIndex); }; CarouselPreviousNext.prototype.rotateSlides = function () { if (!this.isAutoRotationDisabled) { if ( (!this.hasFocus && !this.hasHover && this.isPlayingEnabled) || this.hasUserActivatedPlay ) { this.nextCarouselItem(); } } this.slideTimeout = setTimeout( this.rotateSlides.bind(this), this.timeInterval ); }; CarouselPreviousNext.prototype.updatePlaying = function (play) { this.isPlayingEnabled = play; if (play) { this.pausePlayButtonNode.setAttribute('aria-label', this.pauseLabel); this.pausePlayButtonNode.classList.remove('play'); this.pausePlayButtonNode.classList.add('pause'); this.liveRegionNode.setAttribute('aria-live', 'off'); } else { this.pausePlayButtonNode.setAttribute('aria-label', this.playLabel); this.pausePlayButtonNode.classList.remove('pause'); this.pausePlayButtonNode.classList.add('play'); this.liveRegionNode.setAttribute('aria-live', 'polite'); } }; /* Event Handlers */ CarouselPreviousNext.prototype.handleImageLinkFocus = function () { this.liveRegionNode.classList.add('focus'); }; CarouselPreviousNext.prototype.handleImageLinkBlur = function () { this.liveRegionNode.classList.remove('focus'); }; CarouselPreviousNext.prototype.handleMouseOver = function (event) { if (!this.pausePlayButtonNode.contains(event.target)) { this.hasHover = true; } }; CarouselPreviousNext.prototype.handleMouseOut = function () { this.hasHover = false; }; /* EVENT HANDLERS */ CarouselPreviousNext.prototype.handlePausePlayButtonClick = function () { this.hasUserActivatedPlay = !this.isPlayingEnabled; this.updatePlaying(!this.isPlayingEnabled); }; CarouselPreviousNext.prototype.handlePreviousButtonClick = function () { this.previousCarouselItem(); }; CarouselPreviousNext.prototype.handleNextButtonClick = function () { this.nextCarouselItem(); }; /* Event Handlers for carousel items*/ CarouselPreviousNext.prototype.handleFocusIn = function () { this.liveRegionNode.setAttribute('aria-live', 'polite'); this.hasFocus = true; }; CarouselPreviousNext.prototype.handleFocusOut = function () { if (this.isPlayingEnabled) { this.liveRegionNode.setAttribute('aria-live', 'off'); } this.hasFocus = false; }; /* Initialize Carousel and options */ window.addEventListener( 'load', function () { var carouselEls = document.querySelectorAll('.carousel'); var carousels = []; // set example behavior based on // default setting of the checkboxes and the parameters in the URL // update checkboxes based on any corresponding URL parameters var checkboxes = document.querySelectorAll( '.carousel-options input[type=checkbox]' ); var urlParams = new URLSearchParams(location.search); var carouselOptions = {}; // initialize example features based on // default setting of the checkboxes and the parameters in the URL // update checkboxes based on any corresponding URL parameters checkboxes.forEach(function (checkbox) { var checked = checkbox.checked; if (urlParams.has(checkbox.value)) { var urlParam = urlParams.get(checkbox.value); if (typeof urlParam === 'string') { checked = urlParam === 'true'; checkbox.checked = checked; } } carouselOptions[checkbox.value] = checkbox.checked; }); carouselEls.forEach(function (node) { carousels.push(new CarouselPreviousNext(node, carouselOptions)); }); // add change event to checkboxes checkboxes.forEach(function (checkbox) { var updateEvent; switch (checkbox.value) { case 'moreaccessible': updateEvent = 'setAccessibleStyling'; break; case 'norotate': updateEvent = 'enableOrDisableAutoRotation'; break; } // update the carousel behavior and URL when a checkbox state changes checkbox.addEventListener('change', function (event) { urlParams.set(event.target.value, event.target.checked + ''); window.history.replaceState( null, '', window.location.pathname + '?' + urlParams ); if (updateEvent) { carousels.forEach(function (carousel) { carousel[updateEvent](event.target.checked); }); } }); }); }, false );
ドキュメントへのリンクは次のとおりです:
https://www.w3.org/WAI/ARIA/apg/patterns/
https://www.w3.org/WAI/ARIA/apg/practices/
Mozilla Developer Network のドキュメントは次のとおりです:
https://developer.mozilla.org/en-US/docs/Web/API
ブラウザ プラットフォームを使用して構築します。 Web 標準に従って構築します。アクセシブルなエクスペリエンスを構築します。 Web コンポーネントを使用して構築します。フレームワークなしで構築します。
以上がアクセシビリティ セマンティクスをウィジェットに組み込む - Web Accessibility Initiativeの詳細内容です。詳細については、PHP 中国語 Web サイトの他の関連記事を参照してください。