Technique ARIA10:Using aria-labelledby to provide a text alternative for non-text content

Applicability

This technique applies to HTML with Accessible Rich Internet Applications (WAI-ARIA).

This technique relates to 1.1.1: Non-text Content (Sufficient).

Description

The purpose of this technique is to provide a short description for an element that can be read by assistive technologies (AT) by using the aria-labelledby attribute. The aria-labelledby attribute associates an element with text that is visible elsewhere on the page by using an ID reference value that matches the ID attribute of the labeling element. Assistive technology such as screen readers use the text of the element identified by the value of the aria-labelledby attribute as the text alternative for the element with the attribute.

Examples

Example 1: Providing a short description for a complex graphic

This example shows how to use the aria-labelledby attribute to provide a short text description for a read-only complex graphic of an star rating pattern; the graphic is composed of several image elements. The text alternative for the graphic is the label, visible on the page beneath the star pattern.

<div role="img" aria-labelledby="star_id">
<img src="fullstar.png" alt=""/>
<img src="fullstar.png" alt=""/>
<img src="fullstar.png" alt=""/>
<img src="fullstar.png" alt=""/>
<img src="emptystar.png" alt=""/>
</div>

<div id="star_id">4 of 5</div>

Working example: Providing a short description for a complex graphic.

Other sources

No endorsement implied.

Tests

Procedure

Examine each element where the aria-labelledby attribute is present and the element does not support the alt attribute.
Check whether the value of the aria-labelledby attribute is the id of an element on the web page.
Determine that the text of the element identified by the aria-labelledby attribute accurately labels the element, provides a description of its purpose, or provides equivalent information.

Expected Results

#2 and #3 are true.