vue-use-paginator

Vue 3 composition API hook function to reactively paginate data and arrange paginator buttons. Completely renderless.

Demo

• Live demo
• Demo code

Installation

$ npm install vue-use-paginator

Basic Setup

<script setup lang="ts">
import usePaginator from 'vue-use-paginator'

const {
  page,
  pageSize,
  numPages,
  numItems,
  numButtons,
  slice,
  buttons,
  hasPrev,
  hasNext,
  goStart,
  goPrev,
  goNext,
  goEnd,
} = usePaginator({
  pageSize: 10,
  numItems: 70,
  numButtons: 5,
})
</script>

Details

Hook API

Function usePaginator returns an object of type IPagination which contains the following reactive data plus some convenience functions. You can initialize page, pageSize, numItems and numButtons by passing an object of type IOptions. Otherwise, default initial values will be used.

Name	Type	Description
page	Ref<number>	Current active page (default initial value: 1)
pageSize	Ref<number>	Size of each page (default initial value: 5)
numItems	Ref<number>	Total number of items to paginate (default initial value: 0)
numButtons	Ref<number>	Number of paginator buttons to display (default initial value: 5)
numPages	ComputedRef<number>	Total number of pages
slice	ComputedRef<[number, number]>	Tuple containing start and end index delimiting the currently active page (0 based, end index is exclusive). For example, given you are on page 2, pageSize is 10 and numItems is greater than or equal to 20, slice will be [10, 20].
buttons	ComputedRef<IPaginatorButton[]>	Array of objects usable for displaying paginator buttons (details below)
hasPrev	ComputedRef<boolean>	Whether the currently active page is the first page
hasNext	ComputedRef<boolean>	Whether the currently active page is the last page
goPrev	() => number	Go to next page
goNext	() => number	Go to previous page
goStart	() => 1	Go to first page
goEnd	() => number	Go to last page

• page, pageSize, numItems, as well as numButtons are writable refs that will cause the other reactive properties to adjust when changed. Once you know how many items to paginate, you need to set numItems at least.
• You can move to another page by either calling goPrev, goNext, goStart, goEnd, or by assigning to page directly. Note that assigning a value outside of 1 and numPages will be ignored.

Paginator buttons

When displaying paginator buttons, you often don't have enough slots for each page and therefore need to use a placeholder like '...'. Calculating the positions of these placeholders is not trivial. Luckily, buttons is an array of IPaginatorButton where each item contains the following properties to help you out.

Name	Type	Description
page	number	The page to navigate to when clicking this button
active	boolean	Whether this button shows the currently active page
ellipsis	boolean	Whether this button is a placeholder for omitted pages

Template example

Here is a minimal example how you could write your paginator markup.

<ol>
  <li :class="{ disabled: !hasPrev }" @click="goStart">
    {{ '<<' }}
  </li>
  <li :class="{ disabled: !hasPrev }" @click="goPrev">
    {{ '<' }}
  </li>
  <li
    v-for="button in buttons"
    :key="button.page"
    :class="{ 'current-page': button.active }"
    @click="page = button.page"
  >
    {{ button.ellipsis ? '...' : button.page }}
  </li>
  <li :class="{ disabled: !hasNext }" @click="goNext">
    {{ '>' }}
  </li>
  <li :class="{ disabled: !hasNext }" @click="goEnd">
    {{ '>>' }}
  </li>
</ol>

Notice how certain classes and texts are set based on the values of hasPrev, hasNext, button.active and button.ellipsis. How you style these elements is completely up to you.

API integration

This library doesn't make any assumptions about whether you paginate in the frontend or call a paginated endpoint.

If you paginate in the frontend, just assign the length of your collection to numItems and use the values from slice to slice out the items to display for your current page.

If you call a paginated endpoint, it needs to tell you the total number of items in order to set numItems. You can then use slice or page/pageSize to fetch a page. You will normally want to set up a watcher in order to fetch a new page when page or pageSize changes.

watch([page, pageSize], ([newPage, newPageSize]) => {
  fetchPage(newPage, newPageSize);
})

Types

Definitions

interface IOptions {
  page?: number | Ref<number>
  pageSize?: number | Ref<number>
  numItems?: number | Ref<number>
  numButtons?: number | Ref<number>
}

interface IPagination {
  page: Ref<number>
  pageSize: Ref<number>
  numItems: Ref<number>
  numButtons: Ref<number>
  numPages: ComputedRef<number>
  slice: ComputedRef<[number, number]>
  buttons: ComputedRef<IPaginatorButton[]>
  hasPrev: ComputedRef<boolean>
  hasNext: ComputedRef<boolean>
  goPrev: () => number
  goNext: () => number
  goStart: () => 1
  goEnd: () => number
}

interface IButton {
  page: number
}

interface IPageButton extends IButton {
  active: boolean
  ellipsis: false
}

interface IEllipsisButton extends IButton {
  active: false
  ellipsis: true
}

type IPaginatorButton = IPageButton | IEllipsisButton

Importing Types

import { IOptions, IPagination, IPaginatorButton } from 'vue-use-paginator'