File size: 4,983 Bytes
1e92f2d | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 | # @react-spring/parallax
```bash
yarn add @react-spring/parallax
```
**NOTE**: Currently, only `@react-spring/web` is supported.
`Parallax` creates a scrollable container. `ParallaxLayer`s contain your content and will be moved according to their offsets and speeds.
```jsx
import { Parallax, ParallaxLayer } from '@react-spring/parallax'
const Example = () => {
const ref = useRef()
return (
<Parallax pages={3} ref={ref}>
<ParallaxLayer offset={0} speed={2.5}>
<p>Layers can contain anything</p>
</ParallaxLayer>
<ParallaxLayer offset={1} speed={-2} factor={1.5} horizontal />
<ParallaxLayer sticky={{ start: 1, end: 2 }} />
<ParallaxLayer offset={2} speed={1}>
<button onClick={() => ref.current.scrollTo(0)}>Scroll to top</button>
</ParallaxLayer>
</Parallax>
)
}
```
## Parallax
| Property | Type | Description |
| ----------- | ------------- | ------------------------------------------------------------------------------------------------------- |
| pages | number | Total space of the container. Each page takes up 100% of the viewport. |
| config? | SpringConfig | The spring behavior. Defaults to `config.slow` (see [configs](https://react-spring.io/common/configs)). |
| enabled? | boolean | Whether or not the content can be scrolled. Defaults to `true`. |
| horizontal? | boolean | Whether or not the container scrolls horizontally. Defaults to `false`. |
| innerStyle? | CSSProperties | CSS object to style the inner `Parallax` wrapper (not the scrollable container) |
### `ref` Properties
`Parallax` also has a few useful properties that you can access using a `ref`:
```jsx
const ref = useRef()
...
<Parallax ref={ref}>
```
#### `ref.current.scrollTo`
A function for click-to-scroll. It takes one paramater: the number of the page to scroll to. Pages are zero-indexed, so `scrollTo(0)` will scroll to the first page, `scrollTo(1)` to the second, etc.
#### `ref.current.container`
The `ref` for the outer container `div` of `Parallax`, for when you need access to the actual DOM Element.
**NOTE**: since it is also a `ref`, it must be accessed with `ref.current.container.current`.
#### `ref.current.content`
The `ref` for the inner container `div` of `Parallax`.
### Usage Notes
- All direct `children` of `Parallax` must be `ParallaxLayer`s (or `fragment`s whose only direct `children` are `ParallaxLayer`s).
- `Parallax` is a scrollable container so all scroll events are fired from the container itself -- listening for scroll on `window` won't work (but you _can_ use `ref.current.container`).
## ParallaxLayer
| Property | Type | Description |
| ----------- | ------------ | -------------------------------------------------------------------------------------------------------------------------------------------------- |
| factor? | number | Size of the layer relative to page size (eg: `1` => 100%, `1.5` => 150%, etc). Defaults to `1`. |
| offset? | number | The offset of the layer when it's corresponding page is fully in view (eg: `0` => top of 1st page, `1` => top of 2nd page, etc ). Defaults to `0`. |
| speed? | number | Rate at which the layer moves in relation to scroll. Can be positive or negative. Defaults to `0`. |
| horizontal? | boolean | Whether or not the layer moves horizontally. Defaults to the `horizontal` value of `Parallax` (whose default is `false`). |
| sticky? | StickyConfig | If set, the layer will be 'sticky' between the two offsets. All other props are ignored. Default: `{start?: number = 0, end?: number = start + 1}` |
### Usage Notes
- The `offset` prop is where the layer will end up, not where it begins. For example, if a layer has an offset of `1.5`, it will be halfway down the second page (zero-indexed) when the second page completely fills the viewport.
- The `speed` prop will affect the initial starting position of a layer, but not it's final `offset` position.
- Any layer with `sticky` set will have a `z-index` higher than regular layers. This can be changed manually.
## Demos
- [Parallax - vertical](https://codesandbox.io/s/github/pmndrs/react-spring/tree/main/demo/src/sandboxes/parallax-vert)
- [Parallax - horizontal](https://codesandbox.io/s/github/pmndrs/react-spring/tree/main/demo/src/sandboxes/parallax)
- [Parallax - sticky](https://codesandbox.io/s/github/pmndrs/react-spring/tree/main/demo/src/sandboxes/parallax-sticky)
|