Listing 3.17: use on() for delegation.

Chapter 3/03.js

@@ -13,16 +13,15 @@ $(document).ready(function () {
 
   $('#switcher-default').addClass('selected');
 
-  $('#switcher').click(function (event) {
+  $('#switcher').click(function(event) {
     if ($(event.target).is('button')) {
       var bodyClass = event.target.id.split('-')[1];
 
       $('body').removeClass().addClass(bodyClass);
 
       $('#switcher button').removeClass('selected');
-      $(event.target).addClass('selected');
-    }
-    else {
+        $(event.target).addClass('selected');
+    } else {
       $('#switcher button').toggleClass('hidden');
     }
   });