Lion Web Components

🛠 Status: Pilot Phase

Lion Web Components are still in an early alpha stage; they should not be considered production ready yet.

The goal of our pilot phase is to gather feedback from a private group of users. Therefore, during this phase, we kindly ask you to:

• not publicly promote or link us yet: (no tweets, blog posts or other forms of communication about Lion Web Components)
• not publicly promote or link products derived from/based on Lion Web Components

As soon as Pilot Phase ends we will let you know (feel free to subscribe to this issue https://github.com/ing-bank/lion/issues/1)

Lion web components is a set of highly performant, accessible and flexible Web Components. They provide an unopinionated, white label layer that can be extended to your own layer of components.

Demos

We do have a live Storybook which shows all our components.

How to install

npm i @lion/<package-name>

Content

The accessibility column indicates whether the functionality is accessible in its core. Aspects like styling and content determine actual accessibility in usage.

Package	Version	Description	Accessibility
core		Core System (exports LitElement, lit-html)	n/a
localize		Localize and translate your application/components	n/a
ajax		Fetching data via ajax request	n/a
button		Button	#64
switch		Switch	✔️
calendar		Standalone calendar	#195, #194, #193, #191
icon		Display our svg icons	#173, #172
steps		Multi Step System	n/a
tabs		Move between a small number of equally important views	n/a
-- Forms --
form		Wrapper for multiple form elements	✔️
field		Base Class for all inputs	#190
fieldset		Group for form inputs	✔️
validate		Validation for form components	n/a
checkbox		Checkbox form element	✔️
checkbox-group		Group of checkboxes	✔️
input		Input element for strings	✔️
input-amount		Input element for amounts	#166
input-date		Input element for dates	✔️
input-datepicker		Input element for dates with a datepicker	✔️
input-email		Input element for e-mails	#169
input-iban		Input element for IBANs	#169
radio		Radio from element	✔️
radio-group		Group of radios	✔️
select		Simple native dropdown element	✔️
textarea		Multiline text input	#165
-- Overlays --
overlays		Overlays System using lit-html for rendering	✔️
popup		Popup element	#175, #174
tooltip		Popup element	#178, #177, #176, #175, #174

How to use

Use a Web Component

<script type="module">
  import '@lion/input/lion-input.js';
</script>

<lion-input name="firstName"></lion-input>

Use a JavaScript system

<script type="module">
  import { ajax } from '@lion/ajax';

  ajax.get('data.json').then(response => {
    // most likely you will use response.data
  });
</script>

Extend a Web Component

import { LionInput } from '@lion/input';

class MyInput extends LionInput {}
customElements.define('my-input', MyInput);

Key Features

• High Performance - Focused on great performance in all relevant browsers with a minimal number of dependencies
• Accessibility - Aimed at compliance with the WCAG 2.0 AA standard to create components that are accessible for everybody
• Flexibility - Provides solutions through Web Components and JavaScript classes which can be used, adopted and extended to fit all needs

Technologies

Lion Web Components aims to be future proof and use well-supported proven technology. The stack we have chosen should reflect this.

• lit-html and lit-element
• npm
• yarn
• open-wc
• webpack
• Karma
• Mocha
• Chai
• ESLint
• prettier
• Storybook
• ES modules
• Lots and lots of tests

Rationale

We know from experience that making high quality, accessible UI components is hard and time consuming: it takes many iterations, a lot of development time and a lot of testing to get a generic component that works in every context, supports many edge cases and is accessible in all relevant screen readers.

Lion aims to do the heavy lifting for you. This means you only have to apply your own Design System: by delivering styles, configuring components and adding a minimal set of custom logic on top.

Coding guidlines

Check out our coding guidelines for more detailed information.

How to contribute

Lion Web Components are only as good as its contributions. Read our contribution guide and feel free to enhance/improve Lion. We keep feature requests closed while we're not working on them.

Contact

Feel free to create a github issue for any feedback or questions you might have. You can also find us on the Polymer slack in the #lion channel.

You can join the Polymer slack by visiting Polymer Slack Invite.

Support and issues

As stated above "support and issues time" is currently rather limited: feel free to open a discussion. However, we can not guarantee any response times.