title: How to get the event on changing the selected route displaying in a google render container?
body: <p>Here is the code :</p>
  
  <pre><code>var map = new google.maps.Map(document.getElementById("map_canvas"), $scope.map_options);
  var dirService= new google.maps.DirectionsService();
  var dirRenderer= new google.maps.DirectionsRenderer()
  var dirContainer=document.getElementById('dir-container');
  
  
  var showDirections = function(dirResult, dirStatus) {
                  if (dirStatus != google.maps.DirectionsStatus.OK) {
                      alert('Directions failed: ' + dirStatus);
                      return;
                }
                // Show directions
              dirRenderer.setMap(map);
              dirRenderer.setDirections(dirResult);
              dirRenderer.setPanel(dirContainer);
          };
  
    dirService.route( {origin: '158 cours tolstoi, villeurbanne',
          destination: '8 cours andré philip, villeurbanne',
            travelMode: google.maps.DirectionsTravelMode.DRIVING,
            provideRouteAlternatives: true }
                   , showDirections);
  </code></pre>
  
  <p>I would like to catch the event of selecting another route between the route displaying in the dirContainer.</p>
  
  <p>The alternatives route are displaying in the dirContainer and because provideRouteAlternatives: true.</p>
  
  <p>The event </p>
  
  <pre><code>google.maps.event.addListener(dirRenderer, 'directions_changed', 
                      function() { 
                  alert('a');
              });
  </code></pre>
  
  <p>is not fired when you change the alternative route.</p>
  
  <p>In advance thanks.</p>