title: How can I pass some data from one controller to another peer controller
body: <p>I have the following two peer controllers. There's no parent to these:</p>
  
  <pre><code>&lt;div data-ng-controller="Controller1"&gt;
  
  &lt;/div&gt;
  
  &lt;div data-ng-controller="Controller2"&gt;
     The value of xxx is: {{ xxx }}
  &lt;/div&gt;
  
  angular.module('test')
     .controller('QuestionsStatusController1',
      ['$rootScope', '$scope'
      function ($rootScope, $scope) {
      // How can I set the value of xxx in the HTML that's part of Controller2    
      }]);
  
  angular.module('test')
     .controller('QuestionsStatusController2',
      ['$rootScope', '$scope',
      function ($rootScope, $scope) {
      }]);
  </code></pre>
  
  <p>In controller 1 I want to update the value of the variable xxx in the HTML that's controlled by Controller2. Is there a way I can do this?</p>