<script>
  angular.module('checkboxExample', [])
    .controller('ExampleController', ['$scope', Function($scope) {
      $scope.value1 = true;
      $scope.value2 = 'YES'
    }]);
</script>
<form name="myForm" ng-controller="ExampleController">
  Value1: <input Type="checkbox" ng-model="value1"> <br/>
  Value2: <input Type="checkbox" ng-model="value2"
                 ng-true-value="'YES'" ng-false-value="'NO'"> <br/>
  <tt>value1 = {{value1}}</tt><br/>
  <tt>value2 = {{value2}}</tt><br/>
</form>

it('should change state', Function() {
  var value1 = element(by.binding('value1'));
  var value2 = element(by.binding('value2'));

  expect(value1.getText()).toContain('true');
  expect(value2.getText()).toContain('YES');

  element(by.model('value1')).click();
  element(by.model('value2')).click();

  expect(value1.getText()).toContain('false');
  expect(value2.getText()).toContain('NO');});