主题
useIntersectionObserver
检测目标元素的可见性。
¥Detects that a target element's visibility.
示例
用法
¥Usage
vue
<script setup>
import { useIntersectionObserver } from '@vueuse/core'
import { ref } from 'vue'
const target = ref(null)
const targetIsVisible = ref(false)
const { stop } = useIntersectionObserver(
target,
([entry], observerElement) => {
targetIsVisible.value = entry?.isIntersecting || false
},
)
</script>
<template>
<div ref="target">
<h1>Hello world</h1>
</div>
</template>
指令用法
¥Directive Usage
vue
<script setup lang="ts">
import { vIntersectionObserver } from '@vueuse/components'
import { ref } from 'vue'
const root = ref(null)
const isVisible = ref(false)
function onIntersectionObserver([entry]: IntersectionObserverEntry[]) {
isVisible.value = entry?.isIntersecting || false
}
</script>
<template>
<div>
<p>
Scroll me down!
</p>
<div v-intersection-observer="onIntersectionObserver">
<p>Hello world!</p>
</div>
</div>
<!-- with options -->
<div ref="root">
<p>
Scroll me down!
</p>
<div v-intersection-observer="[onIntersectionObserver, { root }]">
<p>Hello world!</p>
</div>
</div>
</template>
类型声明
显示类型声明
typescript
export interface UseIntersectionObserverOptions extends ConfigurableWindow {
/**
* Start the IntersectionObserver immediately on creation
*
* @default true
*/
immediate?: boolean
/**
* The Element or Document whose bounds are used as the bounding box when testing for intersection.
*/
root?: MaybeComputedElementRef | Document
/**
* A string which specifies a set of offsets to add to the root's bounding_box when calculating intersections.
*/
rootMargin?: string
/**
* Either a single number or an array of numbers between 0.0 and 1.
* @default 0
*/
threshold?: number | number[]
}
export interface UseIntersectionObserverReturn extends Pausable {
isSupported: Ref<boolean>
stop: () => void
}
/**
* Detects that a target element's visibility.
*
* @see https://vueuse.org/useIntersectionObserver
* @param target
* @param callback
* @param options
*/
export declare function useIntersectionObserver(
target:
| MaybeComputedElementRef
| MaybeRefOrGetter<MaybeElement[]>
| MaybeComputedElementRef[],
callback: IntersectionObserverCallback,
options?: UseIntersectionObserverOptions,
): UseIntersectionObserverReturn