WAI-ARIA (Web Accessibility Initiative - Accessible Rich Internet Applications) is a set of guidelines developed by the World Wide Web Consortium (W3C) to enhance the accessibility of web content for people with disabilities.

One of the attributes provided by WAI-ARIA is the aria-level attribute, which is used to indicate the hierarchical level of an element within a structure. It is particularly useful in situations where the order of the elements in the HTML source code does not reflect the desired visual presentation.

How does aria-level work?

The aria-level attribute accepts a numerical value that represents the level of the element within a hierarchical structure. The value starts from 1 for the highest-level element and increments by 1 for each subsequent level.

For example, if you have a set of headings (e.g., <h1> to <h6>), you can use the aria-level attribute to adjust the hierarchical relationship of headings that are visually presented out of order. By setting appropriate aria-level values, you can ensure the correct reading order and accessibility for assistive technologies.

When to use aria-level?

While it is generally recommended to ensure the HTML heading order reflects the visual presentation, there are scenarios where aria-level becomes necessary. Here are a few examples:

1. Tabbed interfaces: In tabbed interfaces, the content of each tab may be loaded in a different order in the HTML source code. To maintain the correct reading order, the aria-level attribute can be used on the tab panels to correct the hierarchy.

2. Collapsible sections: When sections of content are collapsible or expandable, the aria-level attribute can be used to ensure that the nested headings within these sections are read in the proper order.

3. Grids or tables: In complex data tables or grids, the aria-level attribute can be used to specify the hierarchical relationship between header cells and data cells, especially when the order is different than the visual presentation.

Conclusion

The aria-level attribute is a powerful tool in WAI-ARIA to ensure that the hierarchy of elements is properly conveyed to assistive technologies, even when the visual presentation order doesn’t match the HTML source order. Though it should be used judiciously and only when necessary, it can significantly improve the accessibility of web content for users with disabilities.

For more information on the aria-level attribute and other accessibility-related guidelines, refer to the W3C WAI-ARIA documentation.

Tags: accessibility, WAI-ARIA