Core Tabs

@nrk/core-tabs converts <button> and <a> elements to keyboard accessible tabs, controlling following tabpanels. Tabs can be nested and easily extended with custom animations or behaviour through the tabs.toggle event.

Example

<!--demo-->
<core-tabs>
  <button>Tab 1</button>
  <button>Tab 2</button>
  <a href="#link">Tab 3</a>
</core-tabs>
<div>Tabpanel 1</div>
<div hidden>
  <core-tabs>
    <button>Subtab 1</button>
    <button>Subtab 2</button>
    <button>Subtab 3</button>
  </core-tabs>
  <div>Subtabpanel 1</div>
  <div>Subtabpanel 2</div>
  <div>Subtabpanel 3</div>
</div>
<div hidden>Tabpanel 3</div>

<!--demo-->
<div id="jsx-tabs" class="my-vertical-tabs"></div>
<script type="text/jsx">
  ReactDOM.render(<div>
    <CoreTabs>
      <button>Vertical tab 1 JSX</button>
      <button>Vertical tab 2 JSX</button>
    </CoreTabs>
    <div>Tabpanel 1 JSX</div>
    <div>
      <CoreTabs>
        <button>Subtab 1 JSX</button>
        <button hidden>Subtab 2 JSX</button>
      </CoreTabs>
      <div>Subtabpanel 1</div>
      <div hidden>Subtabpanel 2</div>
    </div>
  </div>, document.getElementById('jsx-tabs'))
</script>

Installation

Using NPM provides own element namespace and extensibility. Recommended:

npm install @nrk/core-tabs  # Using NPM

Using static registers the custom element with default name automatically:

<script src="https://static.nrk.no/core-components/major/7/core-tabs/core-tabs.min.js"></script>  <!-- Using static -->

Usage

HTML / JavaScript

<core-tabs>
  <button>Tab 1</button>                  <!-- Tab elements must be <a> or <button>. Do not use <li> -->
  <a href="#">Tab 2</a>
  <button>Tab 3</button>
  <button for="panel-2">Tab 4</button>    <!-- Point to a specific tabpanel -->
</core-tabs>
<div>Tabpanel 1 content</div>             <!-- First tabpanel is the next element sibling of core-tabs -->
<div hidden>Tabpanel 2 content</div>      <!-- Second tabpanel. Use hidden attribute to prevent FOUC -->
<div hidden id="panel-2">Tabpanel 3 content</div>      <!-- Third tabpanel. ID used to connect to tab 4 -->

import CoreTabs from '@nrk/core-tabs'                 // Using NPM
window.customElements.define('core-tabs', CoreTabs)   // Using NPM. Replace 'core-tabs' with 'my-tabs' to namespace
 
const myTabs = document.querySelector('core-tabs')
 
// Getters
myTabs.tab        // Get active tab
myTabs.tabs       // Get all tabs
myTabs.panel      // Get active tabpanel
myTabs.panels     // Get all tabpanels
 
// Setters
myTabs.tab = 0        // Set active tab from index
myTabs.tab = 'my-tab' // Set active tab from id
myTabs.tab = myTab    // Set active tab from element

React / Preact

import CoreTabs from '@nrk/core-tabs/jsx'
 
<CoreTabs
  for={Number|String}           // Optional. Sets active tab from number or id
  onTabsToggle={Function}>      // Optional. Listen to toggle event
  <button>Tab 1</button>        // Tab elements must be <a> or <button>. Do not use <li>
  <a href="#">Tab 2</a>
</CoreTabs>
<div>Tabpanel 1 content</div>             // First tabpanel is the next element sibling of CoreTabs
<div hidden>Tabpanel 1 content</div>      // Second tabpanel. Use hidden attribute to prevent FOUC
<div hidden>Tabpanel 1 content</div>      // Third tabpanel.  Use hidden attribute to prevent FOUC

Events

tabs.toggle

Fired when toggling a tab:

document.addEventListener('tabs.toggle', (event) =>
  event.target     // The tabs element
})

Styling

All styling in documentation is example only. Both the tabs and tabpanels receive attributes reflecting the current toggle state:

.my-tab {}                          /* Target tab in any state */
.my-tab[aria-selected="true"] {}    /* Target only open tab */
.my-tab[aria-selected="false"] {}   /* Target only closed tab */
 
.my-tabpanel {}                     /* Target panel element in any state */
.my-tabpanel:not([hidden]) {}       /* Target only open panel */
.my-tabpanel[hidden] {}             /* Target only closed panel */

FAQ

Why aren't tabs wrapped in `<ul><li>...</li></ul>`?

A <ul>/<li> structure would seem logical for tabs, but this causes some screen readers to incorrectly announce tabs as single (tab 1 of 1).

Does panels always need be a next element sibling?

The aria specification does not allow any elements that are focusable by a screen reader to be placed between tabs and panels. Therefore, core-tabs defaults to use the next element siblings as panels. This behaviour can be overridden, by setting up id on panel elements and the for attribute on tab element. Use with caution and only do this if your project must use another DOM structure. Example:

const myTabs = document.querySelector('core-tabs')
myTabs.tabs.forEach((tabs, index) => tab.setAttribute('for', myTabs.panels[index].id = 'my-panel-' + index))

npm

@nrk/core-tabs

Core Tabs

Example

Installation

Usage

HTML / JavaScript

React / Preact

Events

tabs.toggle

Styling

FAQ

Why aren't tabs wrapped in `<ul><li>...</li></ul>`?

Does panels always need be a next element sibling?

Keywords

install

weekly downloads

version

license

homepage

repository

last publish

collaborators

@nrk/core-tabs

Core Tabs

Example

Installation

Usage

HTML / JavaScript

React / Preact

Events

tabs.toggle

Styling

FAQ

Why aren't tabs wrapped in <ul><li>...</li></ul>?

Does panels always need be a next element sibling?

Keywords

install

Downloadsweekly downloads

version

license

homepage

repository

last publish

collaborators

Why aren't tabs wrapped in `<ul><li>...</li></ul>`?

weekly downloads