Skip to content
Home

HeightAnimation

Info
Demos
Properties
Events

Import

import { HeightAnimation } from '@dnb/eufemia'

Description

The HeightAnimation component calculates the height, and animates from auto to auto – or from 0 to auto in height – powered by CSS transition. It calculates the height on the fly.

When the animation is done, it sets the element's height to auto.

The component can be used as an opt-in replacement instead of vanilla HTML Elements.

The element animation is done with a CSS transition with 400ms in duration.

It also re-calculates and changes the height, when the given content changes.

Relevant links

Server-side rendering (SSR)

HeightAnimation is SSR-compatible. When open is true (the default), the component renders its content with the --is-visible class during server-side rendering so the initial HTML is correct without waiting for JavaScript.

Custom duration and delay props are applied after hydration via a DOM effect to avoid hydration mismatches caused by differences in how React serializes CSS custom properties on the server versus the client.

Accessibility

It is important to never animate from 0 to e.g. 64px – because:

  • The content may differ based on the viewport width (screen size)
  • The content itself may change
  • The user may have a larger font-size

Demos

Animation during height changes

This example shows how you easily can enhance the user experience. Here we also use showOverflow to avoid hidden overflow during the animation.

Look at me 👀

const Example = () => {
  const [showMe, setShowMe] = useState(true)
  return (
    <>
      <HeightAnimation showOverflow>
        {showMe ? (
          <Button
            onClick={() => {
              setShowMe(!showMe)
            }}
          >
            Click me!
          </Button>
        ) : (
          <Anchor
            onClick={() => {
              setShowMe(!showMe)
            }}
          >
            No, click me!
          </Anchor>
        )}
      </HeightAnimation>

      <P top>Look at me 👀</P>
    </>
  )
}
render(<Example />)

Basic open/close

This example removes its given children, when open is open={false}.

Look at me 👀

const Example = () => {
  const [openState, setOpenState] = useState(false)
  const [contentState, setContentState] = useState(false)
  const onChangeHandler = ({ checked }) => {
    setOpenState(checked)
  }
  return (
    <>
      <ToggleButton checked={openState} onChange={onChangeHandler} right>
        Open/close
      </ToggleButton>
      <ToggleButton
        checked={contentState || !openState}
        disabled={!openState}
        onChange={({ checked }) => {
          setContentState(checked)
        }}
        space={{
          top: true,
          bottom: true,
        }}
      >
        Change height inside
      </ToggleButton>

      <Section variant="information" top>
        <HeightAnimation open={openState}>
          <Section
            innerSpace={{
              block: 'large',
            }}
            variant="information"
          >
            <P space={0}>Your content</P>
          </Section>
          {contentState && <P space={0}>More content</P>}
        </HeightAnimation>
      </Section>

      <P top>Look at me 👀</P>
    </>
  )
}
render(<Example />)

Keep in DOM

When providing keepInDOM={true}, your nested content will never be removed from the DOM. But rather be "hidden" with visually: hidden and aria-hidden.

Your content

const Example = () => {
  const [openState, setOpenState] = useState(true)
  const [contentState, setContentState] = useState(false)
  const onChangeHandler = ({ checked }) => {
    setOpenState(checked)
  }
  return (
    <>
      <ToggleButton checked={openState} onChange={onChangeHandler} right>
        Open/close
      </ToggleButton>
      <ToggleButton
        checked={contentState || !openState}
        disabled={!openState}
        onChange={({ checked }) => {
          setContentState(checked)
        }}
        space={{
          top: true,
          bottom: true,
        }}
      >
        Change height inside
      </ToggleButton>

      <StyledSection variant="information" top>
        <HeightAnimation open={openState} keepInDOM={true} duration={1000}>
          <Section
            innerSpace={{
              block: 'large',
            }}
            variant="information"
          >
            <P space={0}>Your content</P>
          </Section>
          {contentState && <P space={0}>More content</P>}
        </HeightAnimation>
      </StyledSection>
    </>
  )
}
const StyledSection = styled(Section)`
  .content-element {
    transition: transform 1s var(--easing-default);
    transform: translateY(-2rem);

    padding: 4rem 0;
  }

  .dnb-height-animation--parallax .content-element {
    transform: translateY(0);
  }
`
render(<Example />)