I have a boolean value that I want to update on a button click. Looking at the console.log() that I put in, I can see that the value does change as I expect it to, but the value doesn’t change on the front end in the webpart. It stays at the default “true” value. How do I get the value on the front end to change, based on what the state of the boolean is?

import { Version } from '@microsoft/sp-core-library';
import { BaseClientSideWebPart, 
  IPropertyPaneConfiguration, 
  PropertyPaneTextField } from '@microsoft/sp-webpart-base';

import styles from './LoginWireTestWebPart.module.scss';
import * as strings from 'GetlistofalllistsWebPartStrings';

export interface ITesting {
  clickHandler : () => void
}

export interface ILoginWireTestWebPartProps {
}

function log (){
  console.log("before -->", testBool)
  testBool = !testBool
  console.log("after -->", testBool)
}

var testBool : boolean = true;

export default class LoginWireTestWebPart extends BaseClientSideWebPart<ILoginWireTestWebPartProps> {
  public render(): void {
    this.domElement.innerHTML = `
    <button class="btn btn-success" id="testingButton" > <h1> TESTING </h1> </button>
    <br>
    <br>
    ${testBool}

    <div class="${ styles.loginWireTest }"></div>
    `;
    this._setButtonEventHandler();
  }

  protected onInit(): Promise<void> {
    return super.onInit();
  }

  private _setButtonEventHandler() : void {
    this.domElement.querySelector('#testingButton')?.addEventListener('click', () => {
      log()
    })
  }

  protected get dataVersion(): Version {
    return Version.parse('1.0');
  }

  protected getPropertyPaneConfiguration(): IPropertyPaneConfiguration {
    return {
      pages: [
        {
          header: {
            description: strings.PropertyPaneDescription
          },
          groups: [
            {
              groupName: strings.BasicGroupName,
              groupFields: [
                PropertyPaneTextField('description', {
                  label: strings.DescriptionFieldLabel,
                })
              ]
            }
          ]
        }
      ]
    };
  }

}