app/routes/media/show/index.js
import Route from '@ember/routing/route';
import { get, set } from '@ember/object';
export default Route.extend({
templateName: 'media/show/index',
setupController(controller) {
this._super(...arguments);
const parentRoute = get(this, 'routeName').split('.').slice(0, 2).join('.');
const parentController = this.controllerFor(parentRoute);
set(controller, 'parent', parentController);
}
});