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Dynamic props

packages/popmotion-pose/docs/learn/react/dynamic-props.md

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React Pose has been deprecated in favour of Framer Motion. Read the upgrade guide

Dynamic pose props

Each pose property can be set as a function that resolves when the pose is entered:

javascript
const Box = posed.div({
  visible: {
    x: 0,
    y: (props) => 100, // Resolved on `visible` enter
    transition: {
      x: { type: 'tween' },
      y: (props) => ({ type: 'spring' }) // Resolved on `visible` enter
    }
  }
})

By using the provided props argument, this allows us to create dynamic properties that will react to changes in your app.

<TOC />

Props

So what are props? They're just component props! Any props you provide to your posed component will be forwarded to these dynamic pose props.

For instance, you could use a component's i index prop to write a dynamic delay prop:

javascript
const Item = posed.li({
  visible: {
    opacity: 1,
    transition: ({ i }) => ({ delay: i * 50 })
  },
  props: { i: 0 }
});

export default ({ i, isVisible }) =>
  <Item pose={isVisible ? 'hidden' : 'visible'} i={i} />
<CodePen id="jzXzdz" height="400" />

Transition props

transition works a little differently than other pose props.

If set as a function, the function is run once each for every property being animated.

That function is provided a few extra props, automatically generated by Pose:

  • from: The current state of this value
  • to: The target state defined in the pose
  • velocity: If a numerical value, the current velocity of the value
  • key: The name of the current value
  • prevPoseKey: The name of the pose this value was previously set to

These props can be used to return a different transition definition based on the state of the value:

javascript
const Sidebar = posed.div({
  open: {
    x: '-100%',
    transition: ({ velocity, to }) => velocity < 0
      ? { to: 0 }
      : { to }
  }
});

If transition is a named map, some or all of these can be defined as functions:

javascript
const Sidebar = posed.div({
  open: {
    x: 0,
    opacity: 1,
    transition: {
      x: ({ velocity, to }) => velocity < 0 ? { to: -300 } : { to },
      opacity: { type: 'spring' }
    }
  }
});