This Web page lists ARIA Techniques from Techniques for WCAG 2.0: Techniques and Failures for Web Content Accessibility Guidelines 2.0. Technology-specific techniques do not supplant the general techniques: content developers should consider both general techniques and technology-specific techniques as they work toward conformance.
For information about the techniques, see Introduction to Techniques for WCAG 2.0. For a list of techniques for other technologies, see the Table of Contents.
To improve accessibility, WAI-ARIA provides Web developers with the option to add the following semantic information to Web pages and rich Internet widgets which are then exposed to the browser:
Roles to describe the type of widget presented, such as "menu", "treeitem", "slider" and "progressbar."
Roles to describe the structure of the Web page, such as headings, regions, search areas and navigation areas.
Properties to describe the state widgets are in, such as "checked" for a check box, "haspopup" for a menu that renders a sub-menu or other popup and "expanded/collapsed" for a tree node.
Properties to define live regions of a page that are likely to get updates (such as stock quotes), as well as an interruption policy for those updates. Assistive technologies may present critical updates as soon as they are rendered. However, incidental updates are presented only after completing the current task. For example, a screen reader informs a user of an incidental update only after it finishes reading the current paragraph.
Properties for drag-and-drop that describe drag sources and drop targets
A method to provide keyboard navigation for rich internet widgets.
The combination of these features and the structural information conveyed by the DOM structure allow authors to produce an interoperable solution to assistive technologies. (Source: WAI-ARIA Overview)
User Agent support for WAI-ARIA varies, but overall support for WAI-ARIA is improving. Browsers which support WAI-ARIA map WAI-ARIA roles and properties to platform accessibility APIs.
Firefox 1.5 and Firefox 2.0 partially supports WAI-ARIA, however it requires the use of namespaces, and doesn't support the use of Liveregions.
Firefox 3+ contains better support for WAI-ARIA, including Liveregions.
IE8 partially supports WAI-ARIA.
JAWS 8 and Window-Eyes 5.5+ partially support WAI-ARIA.
Jaws 10+ supports WAI-ARIA.
FireVox, a self-voicing extension to Firefox, also supports WAI-ARIA via direct DOM access.
NVDA partially supports WAI-ARIA.
Using technologies in an Accessibility Supported way is required for conformance claims. Read more about Accessibility Support. The WCAG Working Group plans to review which WAI-ARIA techniques are sufficient when Accessible Rich Internet Application specifications reach W3C recommendation status. Refer to WAI-ARIA Overview for the latest information on the status of WAI-ARIA.
Technologies that support Accessible Rich Internet Applications (WAI-ARIA).
This technique relates to:
See User Agent Support for WAI-ARIA for general information on user agent support.
IE 8 only supports aria-labelledby with a single id value and it partially supports aria-describedby.
The purpose of this technique is to demonstrate how to use the WAI-ARIA aria-describedby property to provide programmatically determined, descriptive information about a user interface element. The aria-describedby property may be used to attach descriptive information to one or more elements through the use of an id reference list. The id reference list contains one or more unique element ids.
Refer to Supporting ARIA in XHTML and HTML 4.01 for information on how to provide WAI-ARIA States and Properties with XHTML and HTML. WAI-ARIA States and Properties is compatible with other languages as well; refer to documentation in those languages.
Note: At this time, WAI-ARIA is a Working Draft. This technique is provided as an advisory technique for organizations that wish to experiment with achieving WCAG conformance using WAI-ARIA. When WAI-ARIA becomes a formal specification and is supported in user agents, it is anticipated that this technique will become a sufficient technique.
This example is coded in XHTML with a MIME type of application:xhtml+xml. This MIME type is not supported in all user agents. The aria-describedby property is added directly into the XHTML markup, and no additional scripting is needed.
Example Code:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1
For Accessible Adaptable Applications//EN"
"http://www.w3.org/WAI/ARIA/schemata/xhtml-aria-1.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en"
<head>
<meta http-equiv="content-type" content="application:xhtml+xml; charset=utf-8" />
<title>Demonstration of aria-describedby property</title>
<style type="text/css">
div.form p { clear:left; margin: 0.3em 0;}
.left {
float:left;
width:400px;
}
.right {
width:100px;
text-align:right;
}
</style>
</head>
<body>
<p>The buttons on this page use the Accessible Rich Internet Applications aria-describedby property
to provide more detailed information about the button action</p>
<div class="form">
<p><span class="left" id="fontDesc" >Select the font faces and sizes to be used on this page</span>
<span class="right"><button id="fontB" onclick="doAction('Fonts');" aria-describedby="fontDesc">
Fonts </button></span></p>
<p><span class="left" id="colorDesc" >Select the colors to be used on this page</span>
<span class="right"><button id="colorB" onclick="doAction('Colors');" aria-describedby="colorDesc">
Colors </button></span></p>
<p><span class="left" id="customDesc" >Customize the layout and styles used on this page</span>
<span class="right"><button id="customB" onclick="doAction('Customize');" aria-describedby="customDesc">
Customize </button></span></p>
</div>
</body>
</html>
This example uses scripting to add an aria-describedby property to buttons on a page. The example creates a buttonIds array variable to hold the ids of the elements that contain description text. The setDescribedBy() function is called from the onload event of the window object.
The setDescribedBy() function loops through all of the button elements and calls setAttribute() on each button element to set the aria-describedby property. Each button's aria-describedby property is set to the id of the element containing its descriptive text.
Using a user agent and/or assistive technology which supports WAI-ARIA, the description will be provided when the user interface controls receive focus.
Example Code:
<head>
<meta http-equiv="content-type" content="text/xhtml; charset=utf-8" />
<title>Demonstration of aria-describedby property</title>
<style type="text/css">
div.form p { clear:left; margin: 0.3em 0;}
.left {
float:left;
width:400px;
}
.right {
width:100px;
text-align:right;
}
</style>
<script type="text/javascript">
//<![CDATA[
// array entries for each button on the page that associates the button id
// with the id of the element containing the text which describes the button
var buttonIds = new Array();
buttonIds["fontB"]= "fontDesc";
buttonIds["colorB"] = "colorDesc";
buttonIds["customB"] = "customDesc";
// function that is run after the page has loaded to set the aria-describedBy
// property on each of the elements referenced by the array of id values
function setDescribedBy(){
if (buttonIds){
var buttons = document.getElementsByTagName("button");
if (buttons){
var buttonId;
for(var i=0; i<buttons.length; i++){
buttonId = buttons[i].id;
if (buttonId && buttonIds[buttonId]){
buttons[i].setAttribute("aria-describedby", buttonIds[buttonId]);
}
}
}
}
}
// simulated action function - currently just displays an alert
function doAction(theAction){
alert("Perform the " + theAction + " action");
}
window.onload=setDescribedBy;
//]]>
</script>
</head>
<body>
<p>The buttons on this page use the Accessible Rich Internet Applications
aria-describedby property to provide more detailed information
about the button action.
</p>
<div class="form">
<p><span class="left" id="fontDesc" >Select the font faces and sizes to be used on this page</span>
<span class="right"><button id="fontB" onclick="doAction('Fonts');"> Fonts </button></span>
</p>
<p><span class="left" id="colorDesc" >Select the colors to be used on this page</span>
<span class="right"><button id="colorB" onclick="doAction('Colors');"> Colors </button></span>
</p>
<p><span class="left" id="customDesc" >Customize the layout and styles used on this page</span>
<span class="right"><button id="customB" onclick="doAction('Customize');"> Customize </button></span>
</p>
</div>
</body>
Resources are for information purposes only, no endorsement implied.
Check that there is an input control having an aria-describedby attribute that references one or more elements via unique id.
Check that the referenced element or elements provide additional information about the input control.
#1 and #2 are true.
If this is a sufficient technique for a success criterion, failing this test procedure does not necessarily mean that the success criterion has not been satisfied in some other way, only that this technique has not been successfully implemented and can not be used to claim conformance.
Technologies that support Accessible Rich Internet Applications (WAI-ARIA).
This technique relates to:
See User Agent Support for WAI-ARIA for general information on user agent support.
The objective of this technique is to indicate in a programmatically determinable way that the completion of a user input field is mandatory. The WAI-ARIA
aria-required
property indicates that user input is required before submission. The aria-required property can have values of "true" or "false". For example, if a user must fill in an address field, then aria-required is set to "true".
Note 1:
The fact that the element is required is often visually presented (such as a sign or symbol after the control). Using the aria-required property in addition to the visual presentation makes it much easier for user agents to pass on this important information to the user in a user agent-specific manner. Refer to Supporting ARIA in XHTML and HTML 4.01 for information on how to provide WAI-ARIA States and Properties with XHTML and HTML. WAI-ARIA States and Properties is compatible with other languages as well; refer to documentation in those languages.
Note 2: At this time, WAI-ARIA is a Working Draft. This technique is provided as an advisory technique for organizations that wish to experiment with achieving WCAG conformance using WAI-ARIA. When WAI-ARIA becomes a formal specification and is supported in user agents, it is anticipated that this technique will become a sufficient technique.
The following example shows an XHTML document using the aria-required property to indicate that a form field must be submitted. The mandatory nature of the field is also indicated in the label as a fallback for user agents that do not support WAI-ARIA.
Example Code:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1
For Accessible Adaptable Applications//EN"
"http://www.w3.org/WAI/ARIA/schemata/xhtml-aria-1.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
xml:lang="en">
<head>
<title>Required Input</title>
</head>
<body>
<h1>Required Input</h1>
<p>The following form input field must be completed by the user
before the form can be submitted.</p>
<form action="http://example.com/submit">
<p>
<label for="test">Test (required)</label>
<input name="ariaexample" id="example" aria-required="true" aria-label="Test"/>
</p>
<p>
<input type="submit" value="Submit" />
</p>
</form>
</body>
</html>
This example uses scripting to add the aria-required property to a form element. The required property is assigned using the setAttribute() API.
The array variable, requiredIds, is created with the ids of the elements which need to be marked as required. The setRequired() function is called from the onload event of the window object.
The setRequired() function loops through all of the ids provided, retrieves the element and assigns the aria-required property of true using the setAttribute() function.
When this page is accessed using Firefox 3.0 or later and a screen reader that supports WAI-ARIA, the screen reader will speak "required" when reading the label for the input fields.
Example Code:
<head>
<script type="text/javascript">
//<![CDATA[
// array or ids on the required fields on this page
var requiredIds = new Array( "firstName", "lastName");
// function that is run after the page has loaded to set the aria-required property on each of the
//elements in requiredIds array of id values
function setRequired(){
if (requiredIds){
var field;
for (var i = 0; i< requiredIds.length; i++){
field = document.getElementById(requiredIds[i]);
field.setAttribute("aria-required", "true");
}
}
}
window.onload=setRequired;
//]]>
</script>
</head>
<body>
<p>Please enter the following data. Required fields have been programmatically identified
as required and marked with an asterisk (*) following the field label.</p>
<form action="submit.php">
<p>
<label for="firstName">First Name *: </label><input type="text" name="firstName"
id="firstName" value="" />
<label for="lastName">Last Name *: </label><input type="text" name="lastName"
id="lastName" value="" />
</p>
</form>
</body>
Resources are for information purposes only, no endorsement implied.
Access a page with mandatory form fields in a user agent that supports the Accessible Rich Internet Applications specification.
Leaving mandatory form fields empty, attempt to submit the form.
Check that that the user agent notifies of the missing information.
Provide values for the mandatory fields.
Check that the user agent allows form submission to proceed.
#3 and #5 are true
If this is a sufficient technique for a success criterion, failing this test procedure does not necessarily mean that the success criterion has not been satisfied in some other way, only that this technique has not been successfully implemented and can not be used to claim conformance.
Technologies that support Accessible Rich Internet Applications (WAI-ARIA).
This technique relates to:
See User Agent Support for WAI-ARIA for general information on user agent support.
The objective of this technique is to provide information about the allowable range of an entry field in a programmatically determinable way. The WAI-ARIA
aria-valuemin
and
aria-valuemax
states provide the minimum and maximum (respectively) values that may be provided by the user. Some user agents will not permit users to enter values outside that range, or will generate a validation error if users do so. The developer is still responsible for providing validation that the value is within the range.
Refer to Supporting ARIA in XHTML and HTML 4.01 for information on how to provide WAI-ARIA States and Properties with XHTML and HTML. WAI-ARIA States and Properties is compatible with other languages as well; refer to documentation in those languages.
Note: At this time, WAI-ARIA is a Working Draft. This technique is provided as an advisory technique for organizations that wish to experiment with achieving WCAG conformance using WAI-ARIA. When WAI-ARIA becomes a formal specification and is supported in user agents, it is anticipated that this technique will become a sufficient technique.
The following spin button allows users to enter a number between 1 and 100 (inclusive).
Example Code:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1
For Accessible Adaptable Applications//EN" "http://www.w3.org/WAI/ARIA/schemata/xhtml-aria-1.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
xml:lang="en">
<head>
<title>Spin Button</title>
</head>
<body>
<h1>Spin Button</h1>
<p>Spin button allows users to enter a number between 1 and 100. It is
implemented as a text input, to which user agents that do not support
ARIA roles fall back.</p>
<form action="http://example.com/submit">
<p><label for="test">Enter a number between 1 and 100</label>
<input name="test" id="test" role="spinbutton"
aria-valuemin="1" aria-valuemax="100" /></p>
<p><input type="submit" value="Submit" /></p>
</form>
</body>
</html>Resources are for information purposes only, no endorsement implied.
Access a page with form fields that require data in a certain range, using a user agent that supports the Accessible Rich Internet Applications specification.
Provide information that is outside the allowable range, and attempt to submit the form.
Check that the user agent notifies the user of the invalid data.
Provide information that is inside the allowable range, and attempt to submit the form.
Check that the user agent accepts the data and allows the submit to proceed.
#3 and #5 are true
If this is a sufficient technique for a success criterion, failing this test procedure does not necessarily mean that the success criterion has not been satisfied in some other way, only that this technique has not been successfully implemented and can not be used to claim conformance.
Techniques are informative—that means they are not required. The basis for determining conformance to WCAG 2.0 is the success criteria from the WCAG 2.0 standard—not the techniques. For important information about techniques, please see the Understanding Techniques for WCAG Success Criteria section of Understanding WCAG 2.0.