/paper-listbox

Primary LanguageHTML

Published on NPM Build status Published on webcomponents.org

<paper-listbox>

<paper-listbox> implements an accessible listbox control with Material Design styling. The focused item is highlighted, and the selected item has bolded text.

<paper-listbox>
  <paper-item>Item 1</paper-item>
  <paper-item>Item 2</paper-item>
</paper-listbox>

An initial selection can be specified with the selected attribute.

<paper-listbox selected="0">
  <paper-item>Item 1</paper-item>
  <paper-item>Item 2</paper-item>
</paper-listbox>

Make a multi-select listbox with the multi attribute. Items in a multi-select listbox can be deselected, and multiple item can be selected.

<paper-listbox multi>
  <paper-item>Item 1</paper-item>
  <paper-item>Item 2</paper-item>
</paper-listbox>

Styling

The following custom properties and mixins are available for styling:

Custom property Description Default
--paper-listbox-background-color Menu background color --primary-background-color
--paper-listbox-color Menu foreground color --primary-text-color
--paper-listbox Mixin applied to the listbox {}

Accessibility

<paper-listbox> has role="listbox" by default. A multi-select listbox will also have aria-multiselectable set. It implements key bindings to navigate through the listbox with the up and down arrow keys, esc to exit the listbox, and enter to activate a listbox item. Typing the first letter of a listbox item will also focus it.

See: Documentation, Demo.

Usage

Installation

npm install --save @polymer/paper-listbox

In an html file

<html>
  <head>
    <script type="module">
      import '@polymer/paper-listbox/paper-listbox.js';
    </script>
  </head>
  <body>
    <paper-listbox>
      <div role="option">item 1</div>
      <div role="option">item 2</div>
      <div role="option">item 3</div>
    </paper-listbox>
  </body>
</html>

In a Polymer 3 element

import {PolymerElement, html} from '@polymer/polymer';
import '@polymer/paper-listbox/paper-listbox.js';

class SampleElement extends PolymerElement {
  static get template() {
    return html`
      <paper-listbox>
        <div role="option">item 1</div>
        <div role="option">item 2</div>
        <div role="option">item 3</div>
      </paper-listbox>
    `;
  }
}
customElements.define('sample-element', SampleElement);

Contributing

If you want to send a PR to this element, here are the instructions for running the tests and demo locally:

Installation

git clone https://github.com/PolymerElements/paper-listbox
cd paper-listbox
npm install
npm install -g polymer-cli

Running the demo locally

polymer serve --npm
open http://127.0.0.1:<port>/demo/

Running the tests

polymer test --npm