Creating custom panels

Panels are pages that show information within Home Assistant and can allow controlling it. Panels are linked from the sidebar and rendered full screen. They have real-time access to the Home Assistant object via JavaScript. Examples of panels in the app are dashboards, Map, Logbook and History.

Besides components registering panels, users can also register panels using the panel_custom component. This allows users to quickly build their own custom interfaces for Home Assistant.

Introduction

Panels are defined as custom elements. You can use any framework that you want, as long as you wrap it up as a custom element. To quickly get started with a panel, create a new file <config>/www/example-panel.js with this content

import "https://unpkg.com/[email protected]/lib/wired-card.js?module";
import {
  LitElement,
  html,
  css,
} from "https://unpkg.com/[email protected]/lit-element.js?module";

class ExamplePanel extends LitElement {
  static get properties() {
    return {
      hass: { type: Object },
      narrow: { type: Boolean },
      route: { type: Object },
      panel: { type: Object },
    };
  }

  render() {
    return html`
      <wired-card elevation="2">
        <p>There are ${Object.keys(this.hass.states).length} entities.</p>
        <p>The screen is${this.narrow ? "" : " not"} narrow.</p>
        Configured panel config
        <pre>${JSON.stringify(this.panel.config, undefined, 2)}</pre>
        Current route
        <pre>${JSON.stringify(this.route, undefined, 2)}</pre>
      </wired-card>
    `;
  }

  static get styles() {
    return css`
      :host {
        background-color: #fafafa;
        padding: 16px;
        display: block;
      }
      wired-card {
        background-color: white;
        padding: 16px;
        display: block;
        font-size: 18px;
        max-width: 600px;
        margin: 0 auto;
      }
    `;
  }
}
customElements.define("example-panel", ExamplePanel);

Then add to your configuration.yaml:

panel_custom:
  - name: example-panel
    # url_path needs to be unique for each panel_custom config
    url_path: redirect-server-controls
    sidebar_title: Example Panel
    sidebar_icon: mdi:server
    module_url: /local/example-panel.js
    config:
      # Data you want to make available to panel
      hello: world

API reference

The Home Assistant frontend will pass information to your panel by setting properties on your custom element. The following properties are set:

Property	Type	Description
hass	object	Current state of Home Assistant
narrow	boolean	if the panel should render in narrow mode
panel	object	Panel information. Config is available as panel.config.

JavaScript versions

The Home Assistant user interface is served to browsers as a modern build and a legacy build for older browsers. Custom panels are loaded in both, so define your custom element with standard JavaScript classes (ES2015 or later). ES5-transpiled custom elements are not supported; the previously documented window.loadES5Adapter() hook has been removed.