ember-check-error

components.my-component.js

import Ember from 'ember';

export default Ember.Component.extend({
  selected: [],
  /* setupConfig: Ember.on('init', function () {
    this._super(...arguments);
    console.log('before', this.get('selected'));
    this.resetSelected();
    console.log('after', this.get('selected'));
  }),*/
  
  init() {
    this._super(...arguments);
    console.log('before', this.get('selected'));
    this.resetSelected();
    console.log('after', this.get('selected'));
  },
  resetSelected() {
    this.set('selected', []);
  }
});

routes.application.js

import Ember from 'ember';

export default Ember.Route.extend({
  setupController(controller, model) {
    this._super(controller, model);
    this.controller.setProperties({
      selectedProduct: null,
      appName: 'Ember Twiddlesss',
      isProductSelected: Ember.computed('selectedProduct', {
        get() {
          let selectedProduct = this.get('selectedProduct');
console.log('isProductSelected', selectedProduct);
          return  selectedProduct && selectedProduct.length > 1;
      	}
      })
    });
  }
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
<div class={{if isProductSelected 'Product selected' 'Product not selected' }}>
fun
</div>

{{my-component selected=selectedProduct}}
 
{{outlet}}
<br>
<br>

templates.components.my-component.hbs

{{yield}}

twiddle.json

{
  "version": "0.13.0",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.16.2",
    "ember-template-compiler": "2.16.2",
    "ember-testing": "2.16.2"
  },
  "addons": {
    "ember-data": "2.16.3"
  }
}