RHElement Element

This is the base element that all other RHElements should extend. It handles setting up a shadow root and applies Shady CSS if it is needed.

To create a new RHElement, use npm run new from the root of the RHElements repo. After answering a few questions, a new element will be generated for you by generator-rhelement.

Here is an example of a new element and how it extends the base RHElement.

import RHElement from "../rhelement/rhelement.js";

class MyElement extends RHElement {

  // The HTML tag name for this element.  This will be passed into `customElements.define()`.
  static get tag() {
    return "my-element";
  }

  // The path to the element's SCSS file.  It is compiled to CSS at build time.
  get styleUrl() {
    return "my-element.scss";
  }

  // The path to the element's template.  This used at build time.
  get templateUrl() {
    return "my-element.html";
  }

  constructor() {
    // The call to super is first and contains a reference to the class itself.
    // This allows the base class to see any of MyElement's static properties.
    super(MyElement);

    // any other work to do during the constructor goes here
  }

  // connectedCallback runs when the element is placed into the DOM.  Note that
  // in dynamic apps, this _can_ happen more than once, for instance if an
  // element is moved from one part of the DOM tree to another.
  connectedCallback() {
    // super's connectedCallback goes first
    super.connectedCallback();

    // any other work to do during connectedCallback goes here
  }
}

RHElement.create(MyElement);

Test

npm run test

Build

npm run build

Demo

From the RHElements root directory, run:

npm start

Code style

RHElement (and all RHElements) use Prettier to auto-format JS and JSON. The style rules get applied when you commit a change. If you choose to, you can integrate your editor with Prettier to have the style rules applied on every save.