App Framework

=============

The app framework provides simple MVC-like building blocks (models, model lists,

views, and controllers) for writing single-page JavaScript applications.

These building blocks can be used together or separately to create apps ranging

in complexity from simple non-interactive views to rich, multiple-view apps with

data binding and full client-server synchronization.

If you've used DocumentCloud's excellent Backbone.js framework, many of the

classes and APIs provided by the app framework will look familiar to you. There

are important differences, though, and the YUI app framework takes full

advantage of YUI's powerful component infrastructure under the hood.

Building Blocks

---------------

The app framework provides the following classes, which can be mixed and matched

in virtually any combination to meet your needs. For simple apps, you may find

that you only need a `View`, or perhaps a `View` and a `Model`. For complex

apps, you may want to use the full stack. It's entirely up to you.

The `Model` class provides an attribute-based data model with APIs for getting,

setting, validating, and syncing attribute values to a persistence layer or

server, as well as events for being notified of model changes.

The `ModelList` class can contain an ordered list of `Model` instances (for

example, todo items in a todo list). It provides a convenient API for working

with a list of models and for adding to, removing from, and sorting the list.

Finally, the `View` class represents a logical piece of an application's user

interface, and is responsible for rendering content. A view instance can be

associated with a particular model instance to allow for refreshing whenever

the model changes. Views may also be nested if desired, or even used as

standalone components with no model associations.

Not Yet Implemented

-------------------

The `Controller` class (coming in YUI 3.4.0 PR2) will provide URL-based routing

using HTML5 `pushState()` or the location hash, making it easy to wire up route

handlers for different application states while providing full back/forward

navigation support and bookmarkable, shareable URLs.

Modules

-------

* `app`: Rollup module that includes all of the following modules. Use this

module when you plan to use the full app framework stack.

* `controller`: Provides the `Y.Controller` class (coming in YUI 3.4.0 PR2).

* `model`: Provides the `Y.Model` class.

* `model-list`: Provides the `Y.ModelList` class.

* `view`: Provides the `Y.View` class.

Examples

--------

See `tests/manual/todo.html` and the corresponding `todo.js` file for an

unskinned but functional example of a simple todo list app built using `Model`,

`ModelList`, and `View`.

Enhanced examples and full documentation will be provided in future preview

releases of YUI 3.4.0.

Change History

--------------

### 3.4.0 PR1

* Initial preview release. API is subject to change before final release, so use

with caution.