Created Y.SubApp class by extending Y.App

app/assets/javascripts/sub-app.js

 'use strict';
 
 YUI.add('sub-app', function(Y) {
 
   /**
     Base class to create sub apps.
 
     A Y.SubApp has the same API as Y.App with a few key differences:
       Routes are pulled into the parent application on registration
       Navigation calls are dispatched to the parent
@@ skipping 13 matching lines @@
     /**
       Overwrites the core Y.App.Base.navigate method to fire a navigation
       event with details to the parent application.
 
       @method navigate
       @param {string} url the sub apps path.
     */
     navigate: function(url, options) {
       this.fire('subNavigate', {
         url: url,
         options: options

[bcsaller, 2013/02/26 22:01:00]

I doubt handling just this is enough to make this system work, we are still
subclassing Router and PjaxBase which tie into history, add push/popState
listeners, etc. 

It seems like App should really move the bulk of its methods into a ViewManager
extension and then app-base could use that. We'd only want [View, ViewManager]
for subapps but I'm  not even sure how much of ViewManager makes sense w/o the
ability to control the URL or manage history.

[gary.poster, 2013/02/26 22:35:45]

I appreciate Ben's concern, and this reflects his original desire to avoid using
Y.App.Base.  I hadn't realized that Router and PjaxBase were mixed in.  I do
like how simple this looks so far though.

I tried to investigate whether we could mitigate this trivially.  PjaxBase does
not integrate if you set html5 to false explicitly, before its initializer is
called.  Maybe that would help? 
http://yuilibrary.com/yui/docs/api/files/pjax_js_pjax-base.js.html#l101

That also turns off the html 5 router connection.
http://yuilibrary.com/yui/docs/api/files/app_js_router.js.html#l160
I suspect/hope that this is less pertinent as long as it is clear that SubApp
users are not supposed to call methods that SubApp does not specifically bless.

We could mask the non-blessed ones, I guess, but having tried that in the past,
that never felt very nice.  We could do a whitelist approach, but this moves
farther and farther into hack land at that point.
It would be interesting to see what we actually use of the App.Base in the
expected usage of a SubApp.

[jeff.pihach, 2013/02/27 05:54:01]

I agree that by subclassing app.base we are including a lot of unnecessary code
but it is looking like 3.10 will bring with it a new App.base which only has the
base app methods at which point we will simply be able to upgrade the version
and all of the unnecessary code will be gone. 

By extending app.base it's my goal to maintain a consistent api across the whole
application and be able to take advantage of library improvements as additional
work is done on it.

In the prototype using this new navigate method was enough to mitigate any
further issues but it's entirely possible that once people start using it we
will run into other use cases which will be easy to tackle at that time.

       });
     },
 
     /**
       Fetches the sub apps routes and adds the namespace to each record.
 
       @method getSubAppRoutes
       @return {array} routes with namespace.
     */
     getSubAppRoutes: function() {
       var routes = this.get('routes'),
           namespace = this.get('urlNamespace'),
           i;
 
-      for (i = 0; i < routes.length; i += 1) {

[bcsaller, 2013/02/26 22:01:00]

We usually use iterators for this.

[gary.poster, 2013/02/26 22:35:45]

+1, unless Jeff has a counter-argument

[jeff.pihach, 2013/02/27 05:54:01]

No counter here - I'll be switching this over

-        routes[i].namespace = namespace;
-      }
+      Y.Array.each(routes, function(route) {
+        route.namespace = namespace;
+      });
 
       return routes;
     },
 
     destructor: function() {}
 
   }, {
     ATTRS: {
       /**
         The namespace of the sub-app to update the browser url under.
 
         @attribute urlNamespace
         @default undefined
         @type {string}
       */
-      urlNamespace: {},
-
-      /**
-        The SubApp's index location in the registration array.
-
-        @attribute index
-        @default undefined
-        @type {integer}
-      */
-      index: {}

[bcsaller, 2013/02/26 22:01:00]

I think this is unused.

[jeff.pihach, 2013/02/27 05:54:01]

Yes it appears your right, consider it gone!

+      urlNamespace: {}
     }
   });
 
 }, '0.1.0', {requires: ['app-base', 'base-build']});