title: How to include an Ionic Directive?
body: <p>I would like to use <a href="http://ionicframework.com/docs/api/directive/ionNavButtons/" rel="nofollow">http://ionicframework.com/docs/api/directive/ionNavButtons/</a> as a way of adjusting what's shown in the header/nav bar based on the route where the elements shown in the header are set in the view.</p>
  
  <pre><code> &lt;!-- The nav bar that will be updated as we navigate --&gt;
  &lt;ion-nav-bar&gt;
  &lt;/ion-nav-bar&gt;
  
  &lt;!-- where the initial view template will be rendered --&gt;
  &lt;ion-nav-view&gt;
    &lt;ion-view&gt;
      &lt;ion-nav-buttons side="left"&gt;
        &lt;button class="button" ng-click="doSomething()"&gt;
          I'm a button on the left of the navbar!
        &lt;/button&gt;
      &lt;/ion-nav-buttons&gt;
      &lt;ion-content&gt;
        Some super content here!
      &lt;/ion-content&gt;
    &lt;/ion-view&gt;
  &lt;/ion-nav-view&gt;
  </code></pre>
  
  <p>However when I try to use that code, the directive is undefined. It must separate from the ionic.js, which I'm including in the page. Is there a special way to add it as a directive or just copy the code from github (<a href="https://raw.githubusercontent.com/driftyco/ionic/master/js/angular/directive/navBar.js" rel="nofollow">https://raw.githubusercontent.com/driftyco/ionic/master/js/angular/directive/navBar.js</a>)? When I just include the directive, I get <code>IonicModule is undefined</code> in the console.</p>