react-springs

(bring your family and friends)

npm install react-springs react rebound --save

Dynamic animations for react/react-native, powered by rebound.

(if you're looking for something more conventional, consider react-ease)

// output floats gradually from 0 to 10
<Spring to={10}>
  {val => <div>{val}</div>}       // yes, children is a function.
</Spring>

// you can compose multiple springs
<Springs to={{left: 20, top: 30}} tension={30} overshootClamping={true}>
  {val => <div style={val}></div>}
</Springs>

// alternately, if you want control on each spring
<Spring to={20} friction={1.5}> {x =>
    <Spring to={30} friction={7}> {y =>
        <div style={{left: x, top: y}}/>}
    </Spring>}
</Spring>

// and if you'd rather not use the child-function pattern
<div>
  <Spring to={20} onSpringUpdate={spring => this.setState({ value: spring.getCurrentValue() })} />
  <div style={{left: this.state.value}}>moving box</div>
</div>

props

• to (Spring): number : sets end value for the spring. if atRest is true, then the spring immediately snaps to to.
• to (Springs): obj : similar to Spring, but accepts a map of key-values.
• from: number : sets start value for a spring. changing it while a spring is in motion will set its current value to from, and continue to to
• atRest: boolean
• friction: number
• tension: number
• overshootClamping: boolean
• onSpringUpdate (Spring): function : optional callback to be notified on every spring movement. 'returns' the spring.
• onSpringUpdate (Springs): function : like Spring, but 'returns' key, spring
• springSystem: SpringSystem : optional instance of rebound's SpringSystem. useful for perf/custom loopers/etc.

dev

npm install

npm start

notes

• don't forget about the ridiculous performance boost you get from React when NODE_ENV=production
• open to ideas on how to set 'velocity' for flings, etc