styled-lit-element

Provides integration with Polymer's LitElement base class.

Features

• Enforces convention to define styles in static get style().
• Automatically renders <style> using the getter content.
• Caches <style> on a class level to prevent unnecessary calculations for each instance.
• Enforces usage of lit-css for style definition.

StyledLitElement

Can be used as an ES class which already extends LitElement.

import { html } from 'lit-html';
import { css } from 'lit-css';
import { StyledLitElement } from 'styled-lit-element';

class FancyBadge extends StyledLitElement {
  static get style() {
    return css`
      :host {
        background-color: blue;
        border-radius: 50%;
        color: white;
        padding: 4px;
      }
    `;
  }

  render() {
    return html`<slot></slot>`;
  }
}

StyledLitElementMixin

Additionally can be used as a conventional ES mixin to control the extension of LitElement. Might be useful if you already have a different base class which extends LitElement.

import { html } from 'lit-html';
import { css } from 'lit-css';
import { LitElement } from '@polymer/lit-element';
import { StyledLitElementMixin } from 'styled-lit-element';

class FancyBadge extends StyledLitElementMixin(LitElement) {
  static get style() {
    return css`
      :host {
        background-color: blue;
        border-radius: 50%;
        color: white;
        padding: 4px;
      }
    `;
  }

  render() {
    return html`<slot></slot>`;
  }
}