https://stackoverflow.com/questions/45234662/ember-could-not-get-select-value-from-template-to-component/45234991

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  bank:{id:''},
  banks:Ember.computed(function(){
    return [{id:1,name:'ABC'},{id:2,name:'DEF'}];
  })
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<select name="bank" class="form-control" id="sel1" onchange={{action (mut bank.id) value="target.value"}}>
        {{#each banks as |bank|}}
        <option value={{bank.id}}>{{bank.name}}</option>
        {{/each}}
        {{log bank.id}}
      </select>
<br>
Selected Bank Id : {{bank.id}}
{{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"
  }
}