HTML Guide for role
A <a> tag element is missing required attributes, depending on other present attributes.
Depending on the use of other HTML attributes, an <a> tag may require additional attributes. For example, when using aria-selected to build a tab list, this is an example of valid code using role, aria-selected, aria-controls and aria-labelledby:
<div class="tab-interface">
<div role="tablist" aria-label="Sample Tabs">
<span
role="tab"
aria-selected="true"
aria-controls="panel-1"
id="tab-1"
tabindex="0">
First Tab
</span>
<span
role="tab"
aria-selected="false"
aria-controls="panel-2"
id="tab-2"
tabindex="-1">
Second Tab
</span>
</div>
<div id="panel-1" role="tabpanel" tabindex="0" aria-labelledby="tab-1">
<p>Content for the first panel</p>
</div>
<div id="panel-2" role="tabpanel" tabindex="0" aria-labelledby="tab-2" hidden>
<p>Content for the second panel</p>
</div>
</div>
The <a> element requires either a href attribute, or a role attribute.
Using aria-required on a div element requires more context about that element, by providing one of the attributes aria-expanded, aria-valuemax, aria-valuemin, aria-valuenow, role.
When possible, you should prefer semantic tags like input, select and textarea, and use the required attribute, but when form controls are created using non-semantic elements, such as a div element, the aria-required attribute should be included with a value of true to indicate to assistive technologies that user input is required on the element for the form to be submittable. In that case, other attributes might be needed to make the element valid.
For example, we could build a radiogroup using a div like this:
<div aria-required="true">
<div data-value="One"></div> 1
<div data-value="Two"></div> 2
<div data-value="Three"></div> 3
</div>
This HTML snippet would then be decorated using CSS and added functionality using JavaScript. However, the W3C validator will complain that the element div is missing one of the attributes aria-expanded, aria-valuemax, aria-valuemin, aria-valuenow, role.
We can fix that by adding the appropiate role to that div element, like this:
<div aria-required="true" role="radiogroup">
<div data-value="One"></div> 1
<div data-value="Two"></div> 2
<div data-value="Three"></div> 3
</div>
Here is an example showing how to add the “role” attribute to the “div” element:
<div role="region">
<!-- Your content goes here -->
</div>
In this example, the role attribute is added with the value radiogroup. You can choose the appropriate ARIA role based on the purpose or role of your div element.
Remember to also provide the necessary values for the specified attributes if you are adding aria-valuemax, aria-valuemin, or aria-valuenow to ensure proper accessibility and usability of your content.
An element is using ARIA attributes, but its role has not been defined. ARIA defines semantics that can be applied to elements, with these divided into roles (defining a type of user interface element) and states and properties that are supported by a role. Authors must assign an ARIA role and the appropriate states and properties to an element during its life-cycle, unless the element already has appropriate ARIA semantics (via use of an appropriate HTML element). Examples:
<!-- This div uses ARIA but its role is not clear, so it's invalid. -->
<div aria-expanded="true">...</div>
<!-- This div defines clearly its role, so it's valid. -->
<div role="navigation" aria-expanded="true">...</div>
<!-- Nav elements have an implicit navigation role so we don't need the role attribute. -->
<nav aria-expanded="true">...</nav>
The article role indicates a section of a page that could easily stand on its own on a page, in a document, or on a website, is implicit when using the <article> tag.
This role indicates a section of a page that could easily stand on its own on a page, in a document, or on a website. It is usually set on related content items such as comments, forum posts, newspaper articles or other items grouped together on one page. It can be added to generic elements like <div> to convey this role, for example:
<div role="article">
<h2>Heading</h2>
<p>Content...</p>
</div>
Instead of using this role, it’s preferrable to use the native <article> element like this:
<article>
<h2>Heading</h2>
<p>Content...</p>
</article>
The <header> HTML element represents introductory content, typically a group of introductory or navigational aids, and has an implicit role of banner, so specifying this role is redundant.
The following example represents a banner using the role attribute:
<div role="banner">
<img src="companylogo.svg" alt="my company name" />
<h1>Title</h1>
<p>Subtitle</p>
</div>
By default, the HTML5 <header> element has an identical meaning to the banner landmark, unless it is a descendant of <aside>, <article>, <main>, <nav>, or <section>, at which point <header> is the heading for that section and not the equivalent of the site-wide banner.
This example uses the <header> element instead of the banner role:
<header>
<img src="companylogo.svg" alt="my company name" />
<h1>Title</h1>
<p>Subtitle</p>
</header>
The button role is used to make an element appear as a button control to a screen reader and can be applied to otherwise non-interactive elements like <div>. If you’re already using a <button> element, then it’s redundant to apply it the role button, as that’s implicit.
<!-- Instead of this -->
<button role="button">Buy</button>
<!-- Do this -->
<button>Buy</button>
The button role is used to make an element appear as a button control to a screen reader and can be applied to otherwise non-interactive elements like <div>. If you’re already using an <input> element whose type is submit, then it’s redundant to apply it the role button, as that’s implicit.
<!-- Instead of this -->
<input type="submit" role="button">Buy</button>
<!-- Do this -->
<input type="submit">Buy</button>
The <summary> HTML element specifies a clickable summary, caption, or legend for a <details> element’s disclosure box. As the <summary> element has an implicit button role, it’s not needed to include it explicitly.
Here’s an example, clicking the <summary> element toggles the state of the parent <details> element open and closed.
<details>
<summary>I have keys but no doors. I have space but no room. You can enter but can’t leave. What am I?</summary>
A keyboard.
</details>
Using the <aside> element will automatically communicate a section has a role of complementary, so specifying the role="complementary" is redundant.