Problem with select ng-option and ng-change in Controller

I have some troubles with select and ng-change: I’m trying to calculate a value with couple of text boxes and two selects.
For some reason Controller gets always default value from the selects even while View seems to have correct user selected value.

This is my View:

<ion-view title="Nitrox calculator">
  <ion-content class="padding">
        <select  ng-model="foo" ng-change="changedValue()" 
             ng-options="foo as for foo in blisterPackTemplates">

        <select  ng-model="bar" ng-change="changedValue()" 
           ng-options="bar as for bar in blisterPackTemplates">

And the Controller:

    angular.module('starter.controllers', [])
    .controller('Calculator', function($scope) {
      var d2 = $;
      var d1 = $;
      $scope.itemListBar.push('d2: ';
      $scope.itemListFoo.push('d1: ';


Function changedValue() has always values of $ and $ “–Select–”.

But in this works as expected.

Maybe this is a bug of ionic framework, I also met this problem during development, probably you can try another way.