Question
Answer and Explanation
Creating accessible tooltips involves careful consideration of both visual and assistive technology users. Here's how you can create an accessible tooltip:
1. Use Proper HTML Structure:
- Use a descriptive element (like a span or button) as the trigger for the tooltip. Avoid using elements like div without proper ARIA roles, and make sure that the content of your trigger element makes sense without the tooltip.
- Associate the tooltip text with the trigger element using ARIA attributes.
2. Implement ARIA Attributes:
- Use aria-describedby on the trigger element, pointing to the ID of the tooltip's container. This allows screen readers to announce the tooltip content when the trigger is focused.
- Use role="tooltip" on the tooltip container element. This signals to assistive technologies that it contains supplementary information.
- Use tabindex="0" to ensure the trigger is focusable, especially if it’s not natively focusable, so all users can reach it via keyboard navigation.
3. Visual Considerations:
- Ensure the tooltip text has sufficient color contrast against its background. This is vital for readability. The contrast ratio should meet WCAG accessibility standards (a minimum of 4.5:1 for normal text and 3:1 for large text).
- Make sure the tooltip does not obscure important content and it should not disappear before the user has had a chance to read it.
- The tooltip should have sufficient padding to prevent text from touching the edges. Consider the user’s ability to target the tooltip with a mouse.
4. Keyboard Accessibility:
- A user should be able to open and close the tooltip using the keyboard. Focus should remain on the trigger while the tooltip is open, but should not go inside the tooltip itself.
- Tooltips should disappear when the user tabs out of the trigger or when the trigger loses focus.
5. Example Code:
<span tabindex="0" aria-describedby="tooltip-example">More Info</span>
<div id="tooltip-example" role="tooltip">
<p class="qa-text">This is an accessible tooltip example.</p>
</div>
6. JavaScript for Show/Hide:
- Use JavaScript to control the visibility of the tooltip, making it visible on focus and hover and invisible otherwise. Manage focus appropriately using the focus and blur events. Make sure your code handles both keyboard and mouse events.
7. Testing:
- Test your tooltip with different screen readers and keyboard navigation to ensure it functions as expected. Also, test with different font sizes for users with visual impairments.
By implementing these steps, you can create tooltips that are not only functional and helpful but also accessible to all users, including those who rely on assistive technologies.