accessibility-checker-engine
Version:
An automated accessibility checking engine for use by other tools
110 lines (93 loc) • 5.07 kB
HTML
<html lang="en-US">
<head>
<title>aria_attribute_conflict - Accessibility Checker Help</title>
<script>
RULE_MESSAGES = {"en-US":{"fail_conflict":"The ARIA attribute \"{0}\" is in conflict with the corresponding HTML attribute \"{1}\"","group":"An ARIA attribute must not conflict with the corresponding HTML attribute"}};
RULE_ID = "aria_attribute_conflict"
</script>
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<link rel="icon" href="https://ibm.com/able/favicon-32x32.png" type="image/png">
<link rel="icon" href="https://ibm.com/able/favicon.svg" type="image/svg+xml">
<link rel="stylesheet" href="../common/help.css" />
<script type="module">
import "https://1.www.s81c.com/common/carbon/web-components/version/v1.35.0/code-snippet.min.js";
import "https://1.www.s81c.com/common/carbon/web-components/version/v1.35.0/list.min.js";
</script>
<script src="https://cdn.jsdelivr.net/npm/marked/marked.min.js"></script>
<script src="../common/help.js"></script>
</head>
<body>
<div class="bx--grid toolHelp">
<div class="bx--row">
<div class="bx--col-sm-4 bx--col-md-8 bx--col-lg-16 toolHead">
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<h3 id="ruleMessage"></h3>
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<div id="locLevel"></div>
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<p id="groupLabel"></p>
</div>
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<div class="bx--row">
<div class="bx--col-sm-4 bx--col-md-5 bx--col-lg-8 toolMain">
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<mark-down><script type="text/plain">
### Why is this important?
Avoid conflicting and confusing assistive technology behavior.
Using **both** an HTML _attribute_ and the associated ARIA _attribute_ with the same semantic meaning on an element can cause a conflict
that allows one of the attributes to override the other.
As stated in the [ARIA 1.2 specification](https://www.w3.org/TR/wai-aria-1.2/#host_general_conflict),
when HTML elements use both ARIA attributes and their HTML equivalents,
browsers (user agents) **must** ignore the ARIA attributes – the native HTML attribute with the same implicit ARIA semantics takes precedence.
Developers may use ARIA _attributes_ in place of their HTML equivalent _attributes_ on certain elements where the ARIA semantics would be expected.
For example, developers may specify `aria-disabled=true` on a button element,
while also implementing the necessary scripting to functionally disable the button, rather than the use the HTML `disabled` attribute.
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<div id="locSnippet"></div>
### What to do
* Remove one of the conflicting HTML or ARIA _attributes_ from the element.
* Review the [Requirements for use of ARIA attributes in place of equivalent HTML attributes](https://www.w3.org/TR/html-aria/#docconformance-attr) table to help determine which attribute to correctly use.
Example correctly using an element with only an ARIA attribute:
```
<label for="phone">* Phone number: </label>
<input type="text" id="phone" name="phone" aria-required="true">
```
</script></mark-down>
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<div id="ruleInfo"></div>
</div>
<div class="bx--col-sm-4 bx--col-md-3 bx--col-lg-4 toolSide">
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<mark-down><script type="text/plain">
### About this requirement
* [IBM 4.1.2 Name, Role, Value](https://www.ibm.com/able/requirements/requirements/#4_1_2)
* [ARIA 1.2 specification - Conflicts with Host Language Semantics](https://www.w3.org/TR/wai-aria-1.2/#host_general_conflict)
* [ARIA in HTML specification](https://www.w3.org/TR/html-aria/#docconformance-attr)
### Who does this affect?
* People using a screen reader, including blind, low vision, and neurodivergent people
* People using text only browser with Braille display
* People with dexterity impairments using voice control
* People using other assistive technologies that expose accessibility information
</script></mark-down>
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</div>
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</body>
</html>