https://stackoverflow.com/questions/45549119/accessing-model-data-members-in-action-need-cast

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  editState: Ember.inject.service(),
  appName: 'Ember Twiddle',
 actions: {
        showJournal(journalId) {                        
            this.set('editState.selectedJournal',this.get('model').findBy('id',journalId));
          console.log('Yes ',this.get('editState.selectedJournal'));
        }
    }
});

routes.application.js

import Ember from 'ember';

export default Ember.Route.extend({
  model(){
    return [{id:'1',name:'BBC'},{id:'2',name:'TV'}];
  }
});

services.edit-state.js

import Ember from 'ember';

export default Ember.Service.extend({
  selectedJournal:{},
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<select class="form-control" id="journal" onchange={{action 'showJournal' value="target.value"}} >
<option value="" disabled="disabled" selected={{unless editState.selectedJournal.id 'selected'}}>Periodicals:</option>
  {{#each model as |journal|}}
    <option value={{journal.id}} selected={{if (eq editState.selectedJournal.id journal.id) 'selected'}}> {{journal.name}}</option> 
  {{/each}}
</select>
<br>
{{outlet}}
<br>
<br>

twiddle.json

{
  "version": "0.12.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.12.0",
    "ember-template-compiler": "2.12.0",
    "ember-testing": "2.12.0"
  },
  "addons": {
    "ember-data": "2.12.1",
    "ember-truth-helpers": "1.3.0"
  }
}