/vue-virtual-scroll-list

⚡️虚拟滚动A vue component support big amount data list with high render performance and efficient.

Primary LanguageJavaScriptMIT LicenseMIT

CIStatus Downloads Version Quality

Table of contents

Advantages

  • Only 3 required props, simple and very easy to use.

  • Big data list with high render performance and efficient.

  • You don't have to care about item size, it will calculate automatic.

Live demo

https://tangbc.github.io/vue-virtual-scroll-list

https://codesandbox.io/s/live-demo-virtual-list-e1ww1

Simple usage

npm install vue-virtual-scroll-list --save

Root component:

<template>
  <div>
    <virtual-list style="height: 360px; overflow-y: auto;" // make list scrollable
      :data-key="'uid'"
      :data-sources="items"
      :data-component="itemComponent"
    />
  </div>
</template>

<script>
  import Item from './Item'
  import VirtualList from 'vue-virtual-scroll-list'

  export default {
    name: 'root',
    data () {
      return {
        itemComponent: Item,
        items: [{uid: 'unique_1', text: 'abc'}, {uid: 'unique_2', text: 'xyz'}, ...]
      }
    },
    components: { 'virtual-list': VirtualList }
  }
</script>

Item component:

<template>
  <div>{{ index }} - {{ source.text }}</div>
</template>

<script>
  export default {
    name: 'item-component',
    props: {
      index: { // index of current item
        type: Number
      },
      source: { // here is: {uid: 'unique_1', text: 'abc'}
        type: Object,
        default () {
          return {}
        }
      }
    }
  }
</script>

More usages or getting start you can refer to these clearly examples.

Props type

Required props

             Prop              Type Description
data-key String|Function The unique key get from data-sources in each data object. Or a function called with each data-source and return their unique key. Its value must be unique in data-sources, it is used for identifying item size.
data-sources Array[Object] The source array built for list, each array data must be an object and has an unique key get or generate for data-key property.
data-component Component The render item component created / declared by vue, and it will use the data object in data-sources as render prop and named: source.

Optional props

Commonly used

           Prop            Type Default Description
keeps Number 30 How many items you are expecting the virtual list to keep rendering in the real dom.
extra-props Object {} Extra props assign to item component that are not in data-sources. Notice: index and source are both occupied inner.
estimate-size Number 50 The estimate size of each item, if it is closer to the average size, the scrollbar length looks more accurately. It is recommended to assign the average that calculate by yourself.
Uncommonly used

               Prop                Type Default Description
start Number 0 Setting scroll position stay start index.
offset Number 0 Setting scroll position stay offset.
scroll Event Emited when scrolling, param (event, range).
totop Event Emited when scrolled to top or left, no param.
tobottom Event Emited when scrolled to bottom or right, no param.
resized Event Emited when item resized (mounted), param (id, size).
direction String vertical Scroll direction, available values are vertical and horizontal
page-mode Boolean false Let virtual list using global document to scroll through the list.
top-threshold Number 0 The threshold to emit totop event, attention to multiple calls.
bottom-threshold Number 0 The threshold to emit tobottom event, attention to multiple calls.
root-tag String div Root element tag name.
wrap-tag String div List wrapper element (role=group) tag name.
wrap-class String List wrapper element class name.
wrap-style Object {} List wrapper element inline style.
item-tag String div Item wrapper element (role=item) tag name.
item-class String Item wrapper element class name.
item-class-add Function A function that you can return extra class (String) to item wrapper element, param (index).
item-style Object {} Item wrapper element inline style.
item-scoped-slots Object {} The $scopedSlots for item component.
header-tag String div For using header slot, header slot wrapper element (role=header) tag name.
header-class String For using header slot, header slot wrapper element class name.
header-style Object {} For using header slot, header slot wrapper element inline style.
footer-tag String div For using footer slot, footer slot wrapper element (role=footer) tag name.
footer-class String For using footer slot, footer slot wrapper element class name.
footer-style Object {} For using using footer slot, footer slot wrapper element inline style.

Public methods

Usefull public methods

You can call these methods via ref:

Method Description
reset() Reset all state back to initial.
scrollToBottom() Manual set scroll position to bottom.
scrollToIndex(index) Manual set scroll position to a designated index.
scrollToOffset(offset) Manual set scroll position to a designated offset.
getSize(id) Get the designated item size by id (from data-key value).
getSizes() Get the total number of stored (rendered) items.
getOffset() Get current scroll offset.
getClientSize() Get wrapper element client viewport size (width or height).
getScrollSize() Get all scroll size (scrollHeight or scrollWidth).
updatePageModeFront() When using page mode and virtual list root element offsetTop or offsetLeft change, you need call this method manually.

Attentions

This component use an in-place patch strategy to render list instead of v-for and :key. This way achieves the best efficient, but only suitable when your list output does not rely on item component inner state or temporary DOM state (e.g. form input values).

But how to deal with such a situation? Without maintaining inner state, recommend to use props and dispatch (stateless component), here is an example keep-state.

Contributions

Welcome to improve this component with any issue, pull request or code review.

Changelogs

Maintain and update occasionally, for changes see release.

License

MIT License.