ionic - ion-nav-buttons ng-click not working

I added a ion-nav-button exactly as documented (direct descendant of the ion-view) and added an ng-click event that isn't firing.

Any idea why?

I attached a plunkr of the issue.

http://plnkr.co/edit/cZ9wDlhJJzebBr1WR3rT?p=preview

Thanks! Uri

<ion-view title="Dashboard">
  <ion-nav-buttons side="right">
    <button class="button" ng-click="alert('signup btn clicked');">
      Signup
    </button>
  </ion-nav-buttons>
  <ion-content class="has-header padding">
    <h1>Ionic scroll</h1>
    <p>On iphone tapping slightly above or below text doesn't open keyboard.</p>
    <input type="text" name="name" style="border: 1px solid grey;">
  </ion-content>
</ion-view>

That's because in the DashController there is no function alert(...); The ng-click="alert('xx') is translated in to $scope.alert('xx');

So if you create in the DashController:

$scope.alert = function(text) {
  alert(text);
}

it will work.