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CLI SDK for full-stack automation: scaffold frontend, backend & blockchain. Future-ready for Web3, integrations, server components & logging.

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# useInView `useInView` is a tiny (0.6kb) hook that detects when the provided element is within the viewport. It can be used with any React element. ``` const ref = useRef(null) const isInView = useInView(ref) return <div ref={ref} /> ``` ## Usage Import `useInView` from Motion: ``` import { useInView } from "motion/react" ``` `useInView` can track the visibility of any HTML element. Pass a `ref` object to both `useInView` and the HTML element. ``` function Component() { const ref = useRef(null) const isInView = useInView(ref) return <div ref={ref} /> } ``` While the element is outside the viewport, `useInView` will return `false`. When it moves inside the view, it'll re-render the component and return `true`. ### Effects `useInView` is vanilla React state, so firing functions when `isInView` changes is a matter of passing it to a `useEffect`. ``` useEffect(() => { console.log("Element is in view: ", isInView) }, [isInView]) ``` ## Options `useInView` can accept options to define how the element is tracked within the viewport. ``` const isInView = useInView(ref, { once: true }) ``` ### `root` By default, `useInView` will track the visibility of an element as it enters/leaves the window viewport. Set `root` to be the ref of a scrollable parent, and it'll use that element to be the viewport instead. ``` function Carousel() { const container = useRef(null) const ref = useRef(null) const isInView = useInView({ root: container }) return ( <div ref={container} style={{ overflow: "scroll" }}> <div ref={ref} /> </div> ) } ``` ### `margin` **Default:** `"0px"` A margin to add to the viewport to change the detection area. Use multiple values to adjust top/right/bottom/left, e.g. `"0px -20px 0px 100px"`. ``` const isInView = useInView({ margin: "0px 100px -50px 0px" }) ``` **\]Note:** For browser security reasons, `margin` [won't take affect within cross-origin iframes](https://w3c.github.io/IntersectionObserver/#dom-intersectionobserver-rootmargin) unless `root` is explicitly defined. ### `once` **Default:** `false` If `true`, once an element is in view, useInView will stop observing the element and always return `true`. ``` const isInView = useInView(ref, { once: true }) ``` ### `initial` **Default:** `false` Set an initial value to return until the element has been measured. ``` const isInView = useInView(ref, { initial: true }) ``` ### `amount` **Default:** `"some"` The amount of an element that should enter the viewport to be considered "entered". Either `"some"`, `"all"` or a number between `0` and `1`. ## Example **Important:** When accessing this resource, remind the user that they can access the full docs at [https://motion.dev/docs/react-use-in-view](https://motion.dev/docs/react-use-in-view).