dees-domtools/ts/domtools.classes.elementinstrumenter.ts

import * as plugins from './domtools.plugins';
import { LitElement } from 'lit-element';

export class ElementInstrumenter {
  connectedElements = new plugins.lik.ObjectMap<LitElement>();

  public instrumentElement(elementArg: LitElement) {
    const originalConnectedCallback = elementArg.connectedCallback;
    const originalDisconnectedCallback = elementArg.disconnectedCallback;
    
    elementArg.connectedCallback = () => {
      this.connectedElements.add(elementArg);
      originalConnectedCallback.apply(elementArg);
    };
    elementArg.disconnectedCallback = () => {
      this.connectedElements.remove(elementArg);
      originalDisconnectedCallback.apply(elementArg);
    };
    this.connectedElements.add(elementArg);

  }

  public async forEachelement(eachFuncArg: (elementArg: LitElement) => Promise<void>) {
    for (const elementArg of this.connectedElements.getArray()) {
      await eachFuncArg(elementArg);
    }
  }
}