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javascriptcssreactjscss-animationskeyframe

Is there any way to pass a variable from ReactJS to a CSS stylesheet?

I'm writing a scrolling ticker with a variable number of components, so I need it to change how far translate3d moves it based on the number of components. The only way I can think to do this is to somehow pass it a number from the JSX file, but I can't find a way to do that. Is there any way to pass the CSS a variable, or some other way to do what I'm wanting?

Solution

  • There are several « CSS in JS » libraries which allows you to add keyframes to your components animations. As you write your styles in your JavaScript, you can directly use your components props/states or some other constants to create your components styles.

    The 3 following libraries have a keyframes support (I've personally been using the first one):

    Styled-Components (GitHub)

    import styled, { keyframes } from 'styled-components';

const rotate360 = keyframes`
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
`;

const Rotate = styled.div`
  display: inline-block;
  animation: ${rotate360} 2s linear infinite;
`;

    Glamor (GitHub)

    import { css } from 'glamor'

let bounce = css.keyframes('bounce', {
  '0%': { transform: 'scale(0.1)', opacity: 0 },
  '60%': { transform: 'scale(1.2)', opacity: 1 },
  '100%': { transform: 'scale(1)' }
})

<div {...css({
  animation: `${bounce} 2s`,
  width: 50, height: 50,
  backgroundColor: 'red'
})}>
  bounce!
</div>

    Aphrodite (GitHub)

    const translateKeyframes = {
  '0%': { transform: 'translateX(0)' },
  '50%': { transform: 'translateX(100px)' },
  '100%': { transform: 'translateX(0)' },
};

const opacityKeyframes = {
  'from': { opacity: 0 },
  'to': { opacity: 1 }
};

const styles = StyleSheet.create({
  zippyHeader: {
    animationName: [translateKeyframes, opacityKeyframes],
    animationDuration: '3s, 1200ms',
    animationIterationCount: 'infinite',
  },
});

<div className={css(styles.zippyHeader)}>...</div>

    More reading about the « CSS in JS » pattern

    Hope that helps! :)