title: AngularJS - Unbind $window of an event from specific directive
body: <p>Inside one of my directives, I use <code>angular.element($window).bind('scroll')</code>. When the directive is destroyed, I then want to <code>unbind</code> it. Normally, I would just do:</p>
  
  <pre><code>$scope.$on('$destroy', function()
  {
      angular.element($window).unbind('scroll');
  });
  </code></pre>
  
  <p>But what if another directive also has binded to the <code>scroll</code> event of the <code>$window</code>, and that event still needs to exist. If I use the <code>unbind</code> above, the other directive's binding is also eliminated. </p>
  
  <p>What are my options?</p>