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Unified Diff: chrome/common/extensions/docs/a11y.html

Issue 10642015: Basic setup for generating app docs (Closed) Base URL: svn://svn.chromium.org/chrome/trunk/src
Patch Set: Created 8 years, 6 months ago
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Index: chrome/common/extensions/docs/a11y.html
diff --git a/chrome/common/extensions/docs/a11y.html b/chrome/common/extensions/docs/a11y.html
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-<!DOCTYPE html><!-- This page is a placeholder for generated extensions api doc. Note:
- 1) The <head> information in this page is significant, should be uniform
- across api docs and should be edited only with knowledge of the
- templating mechanism.
- 3) All <body>.innerHTML is genereated as an rendering step. If viewed in a
- browser, it will be re-generated from the template, json schema and
- authored overview content.
- 4) The <body>.innerHTML is also generated by an offline step so that this
- page may easily be indexed by search engines.
---><html xmlns="http://www.w3.org/1999/xhtml"><head>
- <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
- <link href="css/ApiRefStyles.css" rel="stylesheet" type="text/css">
- <link href="css/print.css" rel="stylesheet" type="text/css" media="print">
- <script type="text/javascript" src="../../../third_party/jstemplate/jstemplate_compiled.js">
- </script>
- <script type="text/javascript" src="../../../../third_party/json_minify/minify-sans-regexp.js">
- </script>
- <script type="text/javascript" src="js/api_page_generator.js"></script>
- <script type="text/javascript" src="js/bootstrap.js"></script>
- <script type="text/javascript" src="js/sidebar.js"></script>
- <title>Accessibility (a11y) - Google Chrome Extensions - Google Code</title></head>
- <body> <div id="devModeWarning" class="displayModeWarning">
- You are viewing extension docs in chrome via the 'file:' scheme: are you expecting to see local changes when you refresh? You'll need run chrome with --allow-file-access-from-files.
- </div>
- <div id="branchWarning" class="displayModeWarning">
- <span>WARNING: This is the <span id="branchName">BETA</span> documentation.
- It may not work with the stable release of Chrome.</span>
- <select id="branchChooser">
- <option>Choose a different version...
- </option><option value="">Stable
- </option><option value="beta">Beta
- </option><option value="dev">Dev
- </option><option value="trunk">Trunk
- </option></select>
- </div>
- <div id="unofficialWarning" class="displayModeWarning">
- <span>WARNING: This is unofficial documentation. It may not work with the
- current release of Chrome.</span>
- <button id="goToOfficialDocs">Go to the official docs</button>
- </div>
- <div id="gc-container" class="labs">
- <!-- SUBTEMPLATES: DO NOT MOVE FROM THIS LOCATION -->
- <!-- In particular, sub-templates that recurse, must be used by allowing
- jstemplate to make a copy of the template in this section which
- are not operated on by way of the jsskip="true" -->
- <!-- /SUBTEMPLATES -->
- <a id="top"></a>
- <div id="skipto">
- <a href="#gc-pagecontent">Skip to page content</a>
- <a href="#gc-toc">Skip to main navigation</a>
- </div>
- <!-- API HEADER -->
- <table id="header" width="100%" cellspacing="0" border="0">
- <tbody><tr>
- <td valign="middle"><a href="http://code.google.com/"><img src="images/code_labs_logo.gif" height="43" width="161" alt="Google Code Labs" style="border:0; margin:0;"></a></td>
- <td valign="middle" width="100%" style="padding-left:0.6em;">
- <form action="http://www.google.com/cse" id="cse" style="margin-top:0.5em">
- <div id="gsc-search-box">
- <input type="hidden" name="cx" value="002967670403910741006:61_cvzfqtno">
- <input type="hidden" name="ie" value="UTF-8">
- <input type="text" name="q" value="" size="55">
- <input class="gsc-search-button" type="submit" name="sa" value="Search">
- <br>
- <span class="greytext">e.g. "page action" or "tabs"</span>
- </div>
- </form>
- <script type="text/javascript" src="https://www.google.com/jsapi"></script>
- <script type="text/javascript">google.load("elements", "1", {packages: "transliteration"});</script>
- <script type="text/javascript" src="https://www.google.com/coop/cse/t13n?form=cse&amp;t13n_langs=en"></script>
- <script type="text/javascript" src="https://www.google.com/coop/cse/brand?form=cse&amp;lang=en"></script>
- </td>
- </tr>
- </tbody></table>
- <div id="codesiteContent" class="">
- <a id="gc-topnav-anchor"></a>
- <div id="gc-topnav">
- <h1>Google Chrome Extensions (<a href="http://code.google.com/labs/">Labs</a>)</h1>
- <ul id="home" class="gc-topnav-tabs">
- <li id="home_link">
- <a href="index.html" title="Google Chrome Extensions home page">Home</a>
- </li>
- <li id="docs_link">
- <a href="docs.html" title="Official Google Chrome Extensions documentation">Docs</a>
- </li>
- <li id="faq_link">
- <a href="faq.html" title="Answers to frequently asked questions about Google Chrome Extensions">FAQ</a>
- </li>
- <li id="samples_link">
- <a href="samples.html" title="Sample extensions (with source code)">Samples</a>
- </li>
- <li id="group_link">
- <a href="http://groups.google.com/a/chromium.org/group/chromium-extensions" title="Google Chrome Extensions developer forum">Group</a>
- </li>
- <li id="so_link">
- <a href="http://stackoverflow.com/questions/tagged/google-chrome-extension" title="[google-chrome-extension] tag on Stack Overflow">Questions?</a>
- </li>
- </ul>
- </div> <!-- end gc-topnav -->
- <div class="g-section g-tpl-170">
- <!-- SIDENAV -->
- <div class="g-unit g-first" id="gc-toc">
- <ul>
- <li><a href="getstarted.html">Getting Started</a></li>
- <li><a href="overview.html">Overview</a></li>
- <li><a href="whats_new.html">What's New?</a></li>
- <li><h2><a href="devguide.html">Developer's Guide</a></h2>
- <ul>
- <li>Browser UI
- <ul>
- <li><a href="browserAction.html">Browser Actions</a></li>
- <li><a href="contextMenus.html">Context Menus</a></li>
- <li><a href="notifications.html">Desktop Notifications</a></li>
- <li><a href="omnibox.html">Omnibox</a></li>
- <li><a href="options.html">Options Pages</a></li>
- <li><a href="override.html">Override Pages</a></li>
- <li><a href="pageAction.html">Page Actions</a></li>
- </ul>
- </li>
- <li>Browser Interaction
- <ul>
- <li><a href="bookmarks.html">Bookmarks</a></li>
- <li><a href="cookies.html">Cookies</a></li>
- <li><a href="devtools.html">Developer Tools</a></li>
- <li><a href="events.html">Events</a></li>
- <li><a href="history.html">History</a></li>
- <li><a href="management.html">Management</a></li>
- <li><a href="tabs.html">Tabs</a></li>
- <li><a href="windows.html">Windows</a></li>
- </ul>
- </li>
- <li>Implementation
- <ul>
- <li class="leftNavSelected">Accessibility</li>
- <li><a href="background_pages.html">Background Pages</a></li>
- <li><a href="content_scripts.html">Content Scripts</a></li>
- <li><a href="xhr.html">Cross-Origin XHR</a></li>
- <li><a href="i18n.html">Internationalization</a></li>
- <li><a href="messaging.html">Message Passing</a></li>
- <li><a href="permissions.html">Optional Permissions</a></li>
- <li><a href="npapi.html">NPAPI Plugins</a></li>
- </ul>
- </li>
- <li>Finishing
- <ul>
- <li><a href="hosting.html">Hosting</a></li>
- <li><a href="external_extensions.html">Other Deployment Options</a></li>
- </ul>
- </li>
- </ul>
- </li>
- <li><h2><a href="apps.html">Packaged Apps</a></h2></li>
- <li><h2><a href="tutorials.html">Tutorials</a></h2>
- <ul>
- <li><a href="tut_debugging.html">Debugging</a></li>
- <li><a href="tut_analytics.html">Google Analytics</a></li>
- <li><a href="tut_oauth.html">OAuth</a></li>
- </ul>
- </li>
- <li><h2>Reference</h2>
- <ul>
- <li>Formats
- <ul>
- <li><a href="manifest.html">Manifest Files</a></li>
- <li><a href="match_patterns.html">Match Patterns</a></li>
- </ul>
- </li>
- <li><a href="permission_warnings.html">Permission Warnings</a></li>
- <li><a href="api_index.html">chrome.* APIs</a></li>
- <li><a href="api_other.html">Other APIs</a></li>
- </ul>
- </li>
- <li><h2><a href="samples.html">Samples</a></h2></li>
- <div class="line"> </div>
- <li><h2>More</h2>
- <ul>
- <li><a href="http://code.google.com/chrome/webstore/docs/index.html">Chrome Web Store</a></li>
- <li><a href="http://code.google.com/chrome/apps/docs/developers_guide.html">Hosted Apps</a></li>
- <li><a href="themes.html">Themes</a></li>
- </ul>
- </li>
- </ul>
- </div>
- <script>
- initToggles();
- </script>
- <div class="g-unit" id="gc-pagecontent">
- <div id="pageTitle">
- <h1 class="page_title">Accessibility (a11y)</h1>
- </div>
- <!-- TABLE OF CONTENTS -->
- <div id="toc">
- <h2>Contents</h2>
- <ol>
- <li>
- <a href="#controls">Use accessible UI controls</a>
- <ol>
- <li>
- <a href="#htmlcontrols">Standard controls</a>
- </li><li>
- <a href="#aria">ARIA in custom controls</a>
- </li><li>
- <a href="#focus">Focus in custom controls</a>
- </li>
- </ol>
- </li><li>
- <a href="#keyboard"> Support keyboard access </a>
- <ol>
- <li>
- <a href="#navigation"> Navigation </a>
- </li><li>
- <a href="#shortcuts"> Shortcuts </a>
- </li>
- </ol>
- </li><li>
- <a href="#more"> Provide accessible content </a>
- <ol>
- <li>
- <a href="#text">Text</a>
- </li><li>
- <a href="#colors">Colors</a>
- </li><li>
- <a href="#sound">Sound</a>
- </li><li>
- <a href="#images">Images</a>
- </li>
- </ol>
- </li><li>
- <a href="#examples">Examples</a>
- <ol>
- </ol>
- </li>
- </ol>
- </div>
- <!-- /TABLE OF CONTENTS -->
- <!-- Standard content lead-in for experimental API pages -->
- <!-- STATIC CONTENT PLACEHOLDER -->
- <div id="static"><div id="pageData-name" class="pageData">Accessibility (a11y)</div>
-<div id="pageData-showTOC" class="pageData">true</div>
-<p>
-When you design an extension,
-try to make it as accessible as possible
-to people with disabilities such as
-visual impairment, hearing loss, and limited dexterity.
-</p>
-<p>
-Everyone — not just people with special needs —
-can benefit from the alternative access modes
-that accessible extensions provide.
-For example, keyboard shortcuts are important
-for blind people and people with limited dexterity,
-but they also help power users get things done
-more quickly without using a mouse.
-Captions and transcripts give deaf people access to audio content,
-but they are also useful to language learners.
-</p>
-<p>
-People can interact with your extension in a variety of ways.
-They might use a standard monitor, keyboard, and mouse,
-or they might use a screen magnifier and just a keyboard.
-Another possibility is a <em>screen reader</em>,
-an assistive application tool that interprets
-what's displayed onscreen
-for a blind or visually impaired user.
-A screen reader might speak out loud or produce Braille output.
-</p>
-<p>
-Although you can't predict what tools people will use,
-by following a few simple guidelines
-you can write an extension that is
-more likely to be accessible to more people.
-The guidelines on this page aren't going to
-make your extension accessible for absolutely everyone,
-but they're a good starting point.
-</p>
-<h2 id="controls">Use accessible UI controls</h2>
-<p>
-First, use UI controls that support accessibility.
-The easiest way to get an accessible control is to use a
-standard HTML control.
-If you need to build a custom control,
-keep in mind that it's much easier
-to make the control accessible from the beginning
-than to go back and add accessibility support later.
-</p>
-<h3 id="htmlcontrols">Standard controls</h3>
-<p>
-Try to use standard HTML UI controls whenever possible.
-Standard HTML controls (shown in the following figure)
-are keyboard accessible, scale easily,
-and are generally understood by screen readers.
-</p>
-<img src="images/a11y/standard-html-controls.png" width="550" height="350" alt="Screenshots and code for button, checkbox, radio, text, select/option, and link">
-<h3 id="aria">ARIA in custom controls</h3>
-<p>
-ARIA is a specification for making UI controls accessible to screen readers
-by means of a standard set of DOM attributes.
-These attributes provide clues to the screen reader
-about the function and current state of controls on a web page.
-ARIA is a
-<a href=" http://www.w3.org/WAI/intro/aria">work in progress at the W3C</a>.
-</p>
-<p>
-Adding ARIA support to custom controls in your extension
-involves modifying DOM elements to add attributes
-Google Chrome uses
-to raise events during user interaction.
-Screen readers respond to these events
-and describe the function of the control.
-The DOM attributes specified by ARIA are classified into
-<em>roles</em>, <em>states</em>, and <em>properties</em>.
-</p>
-<p>
-The ARIA attribute <em>role</em>
-is an indication of the control type
-and describes the way the control should behave.
-It is expressed with the DOM attribute <code>role</code>,
-with a value set to one of the pre-defined ARIA role strings.
-Because ARIA roles are static,
-the role attribute should not change its value.
-</p>
-<p>
-The <a href="http://www.w3.org/WAI/PF/aria/roles">ARIA Role Specification</a>
-holds detailed information on how to pick the correct role.
-For example, if your extension includes a toolbar,
-set the <code>role</code> attribute of the toolbar's DOM element as follows:
-</p>
-<pre>&lt;div role="toolbar"&gt;
-</pre>
-<p>
-ARIA attributes are also used to describe
-the current state and properties of controls of a particular role.
-A <em>state</em> is dynamic and should be updated during user interaction.
-For example, a control with the role "checkbox"
-could be in the states "checked" or "unchecked".
-A <em>property</em> is not generally dynamic,
-but is similar to a state
-in that it expresses specific information about a control.
-For more information on ARIA states and properties,
-refer to the
-<a href="http://www.w3.org/TR/wai-aria/states_and_properties">W3C States and Properties specification</a>.
-</p>
-<p class="note">
-<b>Note:</b>
-You don't have to use
-all of the states and properties available for a particular role.
-</p>
-<p>
-Here's an example of adding
-the ARIA property <code>aria-activedescendant</code>
-to the example toolbar control:
-</p>
-<pre>&lt;div role="toolbar" tabindex="0" aria-activedescendant="button1"&gt;
-</pre>
-<p>
-The
-<a href="http://www.w3.org/WAI/PF/aria/states_and_properties#aria-activedescendant"><code>aria-activedescendant</code></a>
-property specifies which child of the toolbar receives focus
-when the toolbar receives focus.
-In this example, the toolbar's first button
-(which has the <code>id</code> "button1")
-is the child that gets focus.
-The code <code>tabindex="0"</code>
-specifies that the toolbar
-receives focus in document order.
-</p>
-<p>
-Here's the complete specification for the example toolbar:
-</p>
-<pre>&lt;div role="toolbar" tabindex="0" aria-activedescendant="button1"&gt;
- &lt;img src="buttoncut.png" role="button" alt="cut" id="button1"&gt;
- &lt;img src="buttoncopy.png" role="button" alt="copy" id="button2"&gt;
- &lt;img src="buttonpaste.png" role="button" alt="paste" id="button3"&gt;
-&lt;/div&gt;
-</pre>
-<p>
-Once ARIA roles, states, and properties are added to the DOM of a control,
-Google Chrome raises the appropriate events to the screen reader.
-Because ARIA support is still a work in progress,
-Google Chrome might not raise an event for every ARIA property,
-and screen readers might not recognize all of the events being raised.
-You can find more information on ARIA support in Google Chrome in the
-<a href="http://www.chromium.org/developers/design-documents/accessibility#TOC-WAI-ARIA-Support">Chromium Accessibility Design Document</a>.
-</p>
-<p>
-For a quick tutorial on adding ARIA controls to custom controls, see
-<a href="http://www.w3.org/2010/Talks/www2010-dsr-diy-aria/">Dave Raggett's presentation from WWW2010</a>.
-</p><h3 id="focus">Focus in custom controls</h3>
-<p>
-Make sure that operation and navigation controls of your extension
-can receive keyboard focus.
-Operation controls might include
-buttons, trees, and list boxes.
-Navigation controls might include tabs and menu bars.
-</p>
-<p>
-By default, the only elements in the HTML DOM
-that can receive keyboard focus
-are anchors, buttons, and form controls.
-However, setting the HTML attribute <code>tabIndex</code> to <code>0</code>
-places DOM elements in the default tab sequence,
-enabling them to receive keyboard focus.
-For example:
-</p>
-<pre><em>element</em>.tabIndex = 0
-</pre>
-<p>
-Setting <code>tabIndex = -1</code> removes the element from the tab sequence
-but still allows the element to receive keyboard focus programmatically.
-Here's an example of setting keyboard focus:
-</p>
-<pre><em>element</em>.focus();
-</pre>
-<p>
-Ensuring that your custom UI controls include keyboard support
-is important not only for users who don't use the mouse
-but also because screen readers use keyboard focus
-to determine which control to describe.
-</p>
-<h2 id="keyboard"> Support keyboard access </h2>
-<p>
-People should be able to use your extension
-even if they can't or don't want to use a mouse.
-</p>
-<h3 id="navigation"> Navigation </h3>
-<p>
-Check that the user can navigate between
-the different parts of your extension
-without using the mouse.
-Also check that any popups on page actions or browser actions
-are keyboard navigable.
-</p>
-<p id="builtin">
-On Windows, you can use <b>Shift+Alt+T</b>
-to switch the keyboard focus to the toolbar,
-which lets you navigate to the icons of page actions and browser actions.
-The help topic
-<a href="http://www.google.com/support/chrome/bin/static.py?hl=en&amp;page=guide.cs&amp;guide=25799&amp;from=25799&amp;rd=1">Keyboard and mouse shortcuts</a>
-lists all of Google Chrome's keyboard shortcuts;
-details about toolbar navigation
-are in the section <b>Google Chrome feature shortcuts</b>.
-</p>
-<p class="note">
-<b>Note:</b>
-The Windows version of Google Chrome 6 was the first
-to support keyboard navigation to the toolbar.
-Support is also planned for Linux.
-On Mac OS X,
-access to the toolbar is provided through VoiceOver,
-Apple's screenreader.
-</p>
-<p>
-Make sure that it's easy to see
-which part of the interface has keyboard focus.
-Usually a focus outline moves around the interface,
-but if you’re using CSS heavily this outline might be suppressed
-or the contrast might be reduced.
-Two examples of focus outline follow.
-</p>
-<img src="images/a11y/focus-outline-2.png" width="200" height="75" alt="A focus outline on a Search button">
-<br>
-<img src="images/a11y/focus-outline.png" width="400" height="40" alt="A focus outline on one of a series of links">
-<h3 id="shortcuts"> Shortcuts </h3>
-<p>
-Although the most common keyboard navigation strategy involves
-using the Tab key to move focus through the extension interface,
-that's not always the easiest or most efficient way
-to use the interface.
-You can make keyboard navigation easier
-by providing explicit keyboard shortcuts.
-</p>
-<p>
-To implement shortcuts,
-connect keyboard event listeners to your controls.
-A good reference is the DHTML Style Guide Working Group’s
-<a href="http://dev.aol.com/dhtml_style_guide">guidelines for keyboard shortcuts</a>.
-</p>
-<p>
-A good way to ensure discoverability of keyboard shortcuts
-is to list them somewhere.
-Your extension’s
-<a href="options.html">Options page</a>
-might be a good place to do this.
-</p>
-<p>
-For the example toolbar,
-a simple JavaScript keyboard handler could look like the following.
-Note how the ARIA property <code>aria-activedescendant</code>
-is updated in response to user input
-to reflect the current active toolbar button.
-</p>
-<pre>&lt;head&gt;
-&lt;script&gt;
- function optionKeyEvent(event) {
- var tb = event.target;
- var buttonid;
- ENTER_KEYCODE = 13;
- RIGHT_KEYCODE = 39;
- LEFT_KEYCODE = 37;
- // Partial sample code for processing arrow keys.
- if (event.type == "keydown") {
- // Implement circular keyboard navigation within the toolbar buttons
- if (event.keyCode == ENTER_KEYCODE) {
- ExecuteButtonAction(getCurrentButtonID());
- <em>// getCurrentButtonID defined elsewhere </em>
- } else if (event.keyCode == event.RIGHT_KEYCODE) {
- // Change the active toolbar button to the one to the right (circular).
- var buttonid = getNextButtonID();
- <em>// getNextButtonID defined elsewhere </em>
- tb.setAttribute("aria-activedescendant", buttonid);
- } else if (event.keyCode == event.LEFT_KEYCODE) {
- // Change the active toolbar button to the one to the left (circular).
- var buttonid = getPrevButtonID();
- <em>// getPrevButtonID defined elsewhere </em>
- tb.setAttribute("aria-activedescendant", buttonid);
- } else {
- return true;
- }
- return false;
- }
-}
-&lt;/script&gt;
-&lt;div role="toolbar" tabindex="0" aria-activedescendant="button1" id="tb1"
- onkeydown="return optionKeyEvent(event);"
- onkeypress="return optionKeyEvent(event);"&gt;
- &lt;img src="buttoncut" role="button" alt="cut" id="button1"&gt;
- &lt;img src="buttoncopy" role="button" alt="copy" id="button1"&gt;
- &lt;img src="buttonpaste" role="button" alt="paste" id="button1"&gt;
-&lt;/div&gt;
-</pre>
-<h2 id="more"> Provide accessible content </h2>
-<p>
-The remaining guidelines might be familiar
-because they reflect good practices for all web content,
-not just extensions.
-</p>
-<h3 id="text">Text</h3>
-<p>
-Evaluate your use of text in your extension.
-Many people might find it helpful
-if you provide a way to increase the text size within your extension.
-If you are using keyboard shortcuts,
-make sure that they don't interfere with
-the zoom shortcuts built into Google Chrome.
-</p>
-<p>
-As an indicator of the flexibility of your UI,
-apply the <a href="http://www.w3.org/TR/2008/REC-WCAG20-20081211/#visual-audio-contrast-scale">200% test</a>.
-If you increase the text size or page zoom 200%,
-is your extension still usable?
-</p>
-<p>
-Also, avoid baking text into images:
-users cannot modify the size of text displayed as an image,
-and screenreaders cannot interpret images.
-Consider using a web font instead,
-such as one of the fonts collected in the
-<a href="http://code.google.com/apis/webfonts/">Google Font API</a>.
-Text styled in a web font is searchable,
-scales to different sizes,
-and is accessible to people using screen readers.
-</p>
-<h3 id="colors">Colors</h3>
-<p>
-Check that there is sufficient contrast between
-background color and foreground/text color in your extension.
-<a href="http://snook.ca/technical/colour_contrast/colour.html">This contrast checking tool</a>
-checks whether your background and foreground colors
-provide appropriate contrast.
-If you’re developing in a Windows environment,
-you can also enable High Contrast Mode
-to check the contrast of your extension.
-When evaluating contrast,
-verify that every part of your extension that relies on
-color or graphics to convey information is clearly visible.
-For specific images, you can use a tool such as the
-<a href="http://www.vischeck.com/vischeck/">Vischeck simulation tool</a>
-to see what an image looks like in various forms of color deficiency.
-</p>
-<p>
-You might consider offering different color themes,
-or giving the user the ability to customize the color scheme
-for better contrast.
-</p>
-<h3 id="sound">Sound</h3>
-<p>
-If your extension relies upon sound or video to convey information,
-ensure that captions or a transcript are available.
-See the
-<a href="http://www.dcmp.org/ciy/">Described and Captioned Media Program guidelines</a>
-for more information on captions.
-</p>
-<h3 id="images">Images</h3>
-<p>
-Provide informative alt text for your images.
-For example:
-</p>
-<pre>&lt;img src="img.jpg" alt="The logo for the extension"&gt;
-</pre>
-<p>
-Use the alt text to state the purpose of the image
-rather than as a literal description of the contents of an image.
-Spacer images or purely decorative images
-should have blank ("") alt text
-or be removed from the HTML entirely and placed in the CSS.
-</p>
-<p>
-If you must use text in an image,
-include the image text in the alt text.
-A good resource to refer to is the
-<a href="http://www.webaim.org/techniques/alttext/">WebAIM article on appropriate alt text</a>.
-</p><h2 id="examples">Examples</h2>
-<p>
-For an example that implements keyboard navigation and ARIA properties, see
-<a href="http://src.chromium.org/viewvc/chrome/trunk/src/chrome/common/extensions/docs/examples/extensions/news_a11y/">examples/extensions/news_a11y</a>
-(compare it to
-<a href="http://src.chromium.org/viewvc/chrome/trunk/src/chrome/common/extensions/docs/examples/extensions/news/">examples/extensions/news</a>).
-For more examples and for help in viewing the source code,
-see <a href="samples.html">Samples</a>.
-</p></div>
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