useVirtualList
Create virtual lists with ease. Virtual lists (sometimes called virtual scrollers) allow you to render a large number of items performantly. They only render the minimum number of DOM nodes necessary to show the items within the container element by using the wrapper element to emulate the container element's full height.
Demo
 Jump to index 
 Filter list by size 
 Row 0 (small)
 Row 1 (large)
 Row 2 (small)
 Row 3 (large)
 Row 4 (small)
 Row 5 (large)
 Row 6 (small)
 Row 7 (large)
 Row 8 (small)
 Row 9 (large)
 Row 10 (small)
 Row 11 (large)
 Row 12 (small)
 Row 13 (large)
 Row 14 (small)
Usage
Simple list
import { useVirtualList } from '@vueuse/core'
const { list, containerProps, wrapperProps } = useVirtualList(
  Array.from(Array(99999).keys()),
  {
    // Keep `itemHeight` in sync with the item's row.
    itemHeight: 22,
  },
)
import { useVirtualList } from '@vueuse/core'
const { list, containerProps, wrapperProps } = useVirtualList(
  Array.from(Array(99999).keys()),
  {
    // Keep `itemHeight` in sync with the item's row.
    itemHeight: 22,
  },
)
Config
| State | Type | Description | 
|---|---|---|
| itemHeight | number | ensure that the total height of the wrapper element is calculated correctly.* | 
| overscan | number | number of pre-rendered DOM nodes. Prevents whitespace between items if you scroll very quickly. | 
* The itemHeight must be kept in sync with the height of each row rendered. If you are seeing extra whitespace or jitter when scrolling to the bottom of the list, ensure the itemHeight is the same height as the row.
Reactive list
import { useVirtualList, useToggle } from '@vueuse/core'
import { computed } from 'vue'
const [isEven, toggle] = useToggle()
const allItems = Array.from(Array(99999).keys())
const filteredList = computed(() => allItems.filter(i => isEven.value ? i % 2 === 0 : i % 2 === 1))
const { list, containerProps, wrapperProps } = useVirtualList(
  filteredList,
  {
    itemHeight: 22,
  },
)
import { useVirtualList, useToggle } from '@vueuse/core'
import { computed } from 'vue'
const [isEven, toggle] = useToggle()
const allItems = Array.from(Array(99999).keys())
const filteredList = computed(() => allItems.filter(i => isEven.value ? i % 2 === 0 : i % 2 === 1))
const { list, containerProps, wrapperProps } = useVirtualList(
  filteredList,
  {
    itemHeight: 22,
  },
)
<template>
  <p>Showing {{ isEven ? 'even' : 'odd' }} items</p>
  <button @click="toggle">Toggle Even/Odd</button>
  <div v-bind="containerProps" style="height: 300px">
    <div v-bind="wrapperProps">
      <div v-for="item in list" :key="item.index" style="height: 22px">
        Row: {{ item.data }}
      </div>
    </div>
  </div>
</template>
<template>
  <p>Showing {{ isEven ? 'even' : 'odd' }} items</p>
  <button @click="toggle">Toggle Even/Odd</button>
  <div v-bind="containerProps" style="height: 300px">
    <div v-bind="wrapperProps">
      <div v-for="item in list" :key="item.index" style="height: 22px">
        Row: {{ item.data }}
      </div>
    </div>
  </div>
</template>
Component
This function also provides a renderless component version via the@vueuse/components package. Learn more about the usage. <UseVirtualList :list="list" :options="options" height="300px">
  <template #="props">
    <!-- you can get current item of list here -->
    <div style="height: 22px">Row {{ props.data }}</div>
  </template>
</UseVirtualList>
<UseVirtualList :list="list" :options="options" height="300px">
  <template #="props">
    <!-- you can get current item of list here -->
    <div style="height: 22px">Row {{ props.data }}</div>
  </template>
</UseVirtualList>
Type Declarations
export interface UseVirtualListOptions {
  /**
   * item height, accept a pixel value or a function that returns the height
   *
   * @default 0
   */
  itemHeight: number | ((index: number) => number)
  /**
   * the extra buffer items outside of the view area
   *
   * @default 5
   */
  overscan?: number
}
export interface UseVirtualListItem<T> {
  data: T
  index: number
}
export declare function useVirtualList<T = any>(
  list: MaybeRef<T[]>,
  options: UseVirtualListOptions
): {
  list: Ref<UseVirtualListItem<T>[]>
  scrollTo: (index: number) => void
  containerProps: {
    ref: Ref<any>
    onScroll: () => void
    style: Partial<CSSStyleDeclaration>
  }
  wrapperProps: ComputedRef<{
    style: {
      width: string
      height: string
      marginTop: string
    }
  }>
}
export interface UseVirtualListOptions {
  /**
   * item height, accept a pixel value or a function that returns the height
   *
   * @default 0
   */
  itemHeight: number | ((index: number) => number)
  /**
   * the extra buffer items outside of the view area
   *
   * @default 5
   */
  overscan?: number
}
export interface UseVirtualListItem<T> {
  data: T
  index: number
}
export declare function useVirtualList<T = any>(
  list: MaybeRef<T[]>,
  options: UseVirtualListOptions
): {
  list: Ref<UseVirtualListItem<T>[]>
  scrollTo: (index: number) => void
  containerProps: {
    ref: Ref<any>
    onScroll: () => void
    style: Partial<CSSStyleDeclaration>
  }
  wrapperProps: ComputedRef<{
    style: {
      width: string
      height: string
      marginTop: string
    }
  }>
}