react-tween

Tween animation for React components

Demo

Usage

Animate props with Tween.

function Example({ color, ...props }) {
  return (
    <Tween
      style={{ color }}
    >
      {style => (
        <div
          style={{ backgroundColor: style.color }}
        />
      )}
    </Tween>
  );
}

Customize easing, duration, and delay.

import { easeCubicInOut } from 'd3-ease';

function Example({ color, ...props }) {
  return (
    <Tween
      easing={easeCubicInOut}
      delay={1000}
      duration={500}
      style={{ color }}
    >
      {/* ... */}
    </Tween>
  );
}

Animate added or removed items with Tween.TransitionGroup.

• In this example, the collection is a list of meetings.
• When a meeting is added, it fades in (willEnter).
• When a meeting is removed, it fades out (willLeave).

function Example({ meetings, ...props }) {
  return (
    <Tween.TransitionGroup
      styles={meetings.map(meeting => ({
        key: meeting.id,
        style: {
          opacity: 1,
        },
        data: meeting,
      }))}
      willEnter={style => ({ ...style.style, opacity: 0 })}
      willLeave={style => ({ ...style.style, opacity: 0 })}
    >
      {styles => (
        <div>
          {styles.map(style => (
            <div
              key={style.key}
              style={{ opacity: style.style.opacity }}
            >
              {style.data.title}
            </div>
          ))}
        </div>
      )}
    </Tween.TransitionGroup>
  );
}

For Tween.TransitionGroup, each style is a TransitionStyle, which has the following format.

{
  key, // item id
  style: { ... }, // plain style object (same format as style for `Tween`)
  data, // item data
}

willEnter and willLeave are passed TransitionStyles and should return plain style objects.

Synchronizing animations

By default, Tweens animate whenever their styles change. If you want control over when animation begins, set the group prop. If the group prop is set, animation only begins when the value of this prop changes. group is essentially a logical grouping of animations that should run together.

function Example({ color1, color2, invalidationCounter, ...props }) {
  return (
    <div {...props}>
      <Tween
        group={invalidationCounter}
        style={{ color: color1 }}
      >
        {/* ... */}
      </Tween>
      <Tween
        group={invalidationCounter}
        style={{ color: color2 }}
      >
        {/* ... */}
      </Tween>
    </div>
  );
}

Comparison to react-motion

Choose react-tween or react-motion based on whether you want tween or spring animation.

• If you want natural, physical motion, use spring animation.
• If you want to specify a duration, or you do not want a bounce, use tween animation.

Setup

yarn
yarn start
# Visit http://localhost:8080