New Twiddle

components.child-component.js

import Ember from 'ember';
import { task, timeout } from 'ember-concurrency';

export default Ember.Component.extend({
  init() {
    this._super();
    this.set('isStudentSignedIn', true);
  }
});

components.parent-component.js

import Ember from 'ember';

export default Ember.Component.extend({
  init() {
    this._super();
    this.set('showSection', true);
  },
  
  didReceiveAttrs(){
    this._super();
    console.log("logging showSection property");
    console.log(this.get('showSection'));
  }
});

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  isStudentSignedIn: false,
  showSection: false,
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
{{outlet}}
{{parent-component 
  isStudentSignedIn=isStudentSignedIn
  showSection=showSection
}}
<br>
<br>

templates.components.child-component.hbs

{{yield}}
<p> in child component </p>

templates.components.parent-component.hbs

{{yield}}

<p> in parent component </p>
{{#if showSection}}
  {{child-component 
    isStudentSignedIn=isStudentSignedIn
  }}
{{/if}}

twiddle.json

{
  "version": "0.15.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.js",
    "ember": "2.12.2",
    "ember-template-compiler": "3.4.3",
    "ember-testing": "3.4.3"
   },
  "addons": {
    "ember-data": "2.11.0"
  }
}