Heading
Headings are absolutely critical for screen reader users and it's important to correctly set their levels. For example, you should never skip a level (having h2 and not h1 on the same page).
The problem is that levels are a question of context. When you move components with headings around, you need to check if levels still make sense and adjust them if not. That's a lot of mundane work and developers often rather take shortcuts such as using h1 element only.
There is proposal for a native <h> element and document outline algorithm to solve this problem once for all but there is no browser support yet. In meantime, our Heading component uses React Context and implements its own document outline algorithm so developers don't have to think about it.
It is also possible to decouple styles from the underlying h1-h6 DOM elements.
Heading basic usage
Base Web [L1]
Lorem ipsum dolor sit amet, consectetur adipiscing elit. Vestibulum fermentum velit ante, ac fringilla nulla pulvinar in. Aenean ut nisi mattis, lobortis purus vel, aliquet ante. In vel viverra lectus. Vivamus a diam faucibus, rutrum quam a, varius felis. Sed pellentesque sodales libero commodo vestibulum. Phasellus convallis gravida tempor. Sed ut bibendum nisl.
Introduction [L2]
Vivamus vehicula justo suscipit, vestibulum nibh eu, faucibus nisi. Aenean molestie sapien nibh, sed sagittis turpis iaculis id. Nam mollis pulvinar ex eget gravida. Pellentesque fringilla odio a consequat condimentum. Curabitur ut auctor mi. Nunc blandit, tellus quis fringilla sollicitudin, risus libero scelerisque lorem, ut sagittis risus ipsum in nisl.
Quotes [L3]
Cras posuere placerat sem sit amet dignissim. Sed pellentesque sagittis sapien at maximus. Ut at gravida lectus. Suspendisse lectus libero, eleifend vestibulum imperdiet ut, rhoncus eu augue. Pellentesque in vulputate lacus, quis molestie lorem. Aenean sit amet blandit nisi. Nullam molestie mi vel quam vehicula, in cursus eros tempus. Sed placerat turpis vestibulum quam suscipit, eget volutpat massa aliquet.
Subtitle [L4]
Proin et posuere lectus. Curabitur condimentum, mauris in viverra euismod, diam elit porttitor quam, ac dictum diam diam eu mauris. Maecenas viverra, turpis sed commodo hendrerit, quam ipsum finibus mauris, et scelerisque sapien tellus mollis leo. Praesent posuere, felis at sagittis hendrerit, est massa tincidunt risus, eget tempus dolor ligula et odio. Praesent luctus lacus quis tristique semper. Etiam semper lacus non auctor fringilla.
Subtitle [L5]
Vivamus vehicula justo suscipit, vestibulum nibh eu, faucibus nisi. Aenean molestie sapien nibh, sed sagittis turpis iaculis id. Nam mollis pulvinar ex eget gravida. Pellentesque fringilla odio a consequat condimentum. Curabitur ut auctor mi. Nunc blandit, tellus quis fringilla sollicitudin, risus libero scelerisque lorem, ut sagittis risus ipsum in nisl.
Subtitle [L6]
Proin et posuere lectus. Curabitur condimentum, mauris in viverra euismod, diam elit porttitor quam, ac dictum diam diam eu mauris. Maecenas viverra, turpis sed commodo hendrerit, quam ipsum finibus mauris, et scelerisque sapien tellus mollis leo. Praesent posuere, felis at sagittis hendrerit, est massa tincidunt risus, eget tempus dolor ligula et odio. Praesent luctus lacus quis tristique semper. Etiam semper lacus non auctor fringilla.
Motivation [L2]
Vivamus vehicula justo suscipit, vestibulum nibh eu, faucibus nisi. Aenean molestie sapien nibh, sed sagittis turpis iaculis id. Nam mollis pulvinar ex eget gravida. Pellentesque fringilla odio a consequat condimentum. Curabitur ut auctor mi. Nunc blandit, tellus quis fringilla sollicitudin, risus libero scelerisque lorem, ut sagittis risus ipsum in nisl.
Ideally, the user will use the default styles but sometimes it might make sense to set a fixed style no matter in what context the component was placed. You can decouple styles from levels through the styleLevel prop. However, the proper h1, h2 ... h6 hiearchy always stays in place.
Decouple and fix heading styles
Base Web [L1 styled as L4]
Lorem ipsum dolor sit amet, consectetur adipiscing elit. Vestibulum fermentum velit ante, ac fringilla nulla pulvinar in. Aenean ut nisi mattis, lobortis purus vel, aliquet ante. In vel viverra lectus. Vivamus a diam faucibus, rutrum quam a, varius felis. Sed pellentesque sodales libero commodo vestibulum. Phasellus convallis gravida tempor. Sed ut bibendum nisl.
Introduction [L2 styled as L5]
Vivamus vehicula justo suscipit, vestibulum nibh eu, faucibus nisi. Aenean molestie sapien nibh, sed sagittis turpis iaculis id. Nam mollis pulvinar ex eget gravida. Pellentesque fringilla odio a consequat condimentum. Curabitur ut auctor mi. Nunc blandit, tellus quis fringilla sollicitudin, risus libero scelerisque lorem, ut sagittis risus ipsum in nisl.
Quotes [L3 styled as L6]
Cras posuere placerat sem sit amet dignissim. Sed pellentesque sagittis sapien at maximus. Ut at gravida lectus. Suspendisse lectus libero, eleifend vestibulum imperdiet ut, rhoncus eu augue. Pellentesque in vulputate lacus, quis molestie lorem. Aenean sit amet blandit nisi. Nullam molestie mi vel quam vehicula, in cursus eros tempus. Sed placerat turpis vestibulum quam suscipit, eget volutpat massa aliquet.
Motivation [L2 styled as L5]
Proin et posuere lectus. Curabitur condimentum, mauris in viverra euismod, diam elit porttitor quam, ac dictum diam diam eu mauris. Maecenas viverra, turpis sed commodo hendrerit, quam ipsum finibus mauris, et scelerisque sapien tellus mollis leo. Praesent posuere, felis at sagittis hendrerit, est massa tincidunt risus, eget tempus dolor ligula et odio. Praesent luctus lacus quis tristique semper. Etiam semper lacus non auctor fringilla.
HeadingLevel API
Warning any = "Prop types are not shown in dev mode"
extract-react-types is not being run in dev mode for speed reasons. If you need to
see prop types add the environment variable FORCE_EXTRACT_REACT_TYPES
eg:
FORCE_EXTRACT_REACT_TYPES=true yarn start <packageName>FORCE_EXTRACT_REACT_TYPES=true yarn start:<team>
Heading API
Warning any = "Prop types are not shown in dev mode"
extract-react-types is not being run in dev mode for speed reasons. If you need to
see prop types add the environment variable FORCE_EXTRACT_REACT_TYPES
eg:
FORCE_EXTRACT_REACT_TYPES=true yarn start <packageName>FORCE_EXTRACT_REACT_TYPES=true yarn start:<team>