Ionic - item does not bind in nav-bar

I have an icon in the nav-bar that should or should not display the toggle's true / false position. Testing in the view works perfectly but the result does not work in the nav bar. Both pages use the same controller.

index.html - nav-bar

<ion-nav-bar class="bar-stable" ng-controller="DashCtrl">
  <ion-nav-buttons side="right">
    <i class="icon ion-eye" ng-show="vaovivo.valor"></i>
  </ion-nav-buttons>
<ion-nav-bar>

Account.html - toggle

<ion-toggle ng-model="vaovivo.valor" ng-checked="vaovivo.valor">
  Modo ao Vivo
</ion-toggle>

Controllers.js

angular.module ('starter.controllers', [])

.controller('DashCtrl', function($scope,$rootScope) {    
  $scope.vaovivo = {'valor':false}
})