toggle

controllers.application\.js

import Controller from '@ember/controller';
import { action } from '@ember/object';

export default class ApplicationController extends Controller {
  appName = 'Ember Twiddle';

  focused = false;
  disabled = false;

  @action
  toggle() {
    console.log('Toggle');
    this.set("disabled", true);
  }

  @action
  focus() {
    this.set("focused", true);
    console.log('focus - isFocused value: ' + this.get("focused"));
  }

  @action
  blur() {
    this.set("focused", false);
    console.log('blur - isFocused value: ' + this.get("focused"));
  }
}

templates.application\.hbs

<h1>Welcome to {{this.appName}}</h1>
<br>
<br>
<label for="admin-checkbox">Toggle Me</label>
<input id="admin-checkbox" type="checkbox" disabled={{this.disabled}} name="isAdmin" onchange={{this.toggle}} onfocus={{this.focus}} onblur={{this.blur}} />

<div>Focused: {{this.focused}}</div>
{{outlet}}
<br>
<br>

twiddle\.json

{
  "version": "0.17.1",
  "EmberENV": {
    "FEATURES": {},
    "_TEMPLATE_ONLY_GLIMMER_COMPONENTS": false,
    "_APPLICATION_TEMPLATE_WRAPPER": true,
    "_JQUERY_INTEGRATION": true
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.5.1/jquery.js",
    "ember": "3.18.1",
    "ember-template-compiler": "3.18.1",
    "ember-testing": "3.18.1"
  },
  "addons": {
    "@glimmer/component": "1.0.0",
    "ember-data": "3.16.5"
  }
}