title: Call a method on a nested controller
body: <p>I have an Angular app that displays a ui.bootstrap.modal dialog when I click on a certain element. I want to make the modal logic reusable so have separated it into a separate controller. The result (simplified) looks like this:</p>
  
  <pre><code>&lt;div ng-controller="MyController"&gt;
      &lt;button class="btn" ng-click="open()"&gt;Open me!&lt;/button&gt;
      &lt;div ng-controller="ModalController" modal="shouldBeOpen" close="close()" options="opts"&gt;
          ...
      &lt;/div&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>The visibility of the modal is controlled by a property on ModalController:</p>
  
  <pre><code>$scope.shouldBeOpen = true;
  </code></pre>
  
  <p>How can I set that property from the <code>open()</code> method on <code>MyController</code>?</p>