Backbone plugin to add app-wide pub/sub.

or shortcut sub()

Subscribe to a channel.

Backbone.Mediator.subscribe('myView:viewId:view:loaded', this.callback, this);

Backbone.Mediator.sub('myView:viewId:view:loaded', this.callback, this);

Subscribe to a group of channels using wildcards

Backbone.Mediator.subscribe('myView:*:view:loaded', this.callback, this);

Subscribe to a channel once.

// Will be called once only
Backbone.Mediator.subscribeOnce('myView:viewId:view:loaded', this.callback, this);

or shortcut pub()

Execute all callbacks defined for a channel. Any addional argument will be tranfered to the callback.

Backbone.Mediator.publish('myView:viewId:view:loaded', 'myView');

// or

Backbone.Mediator.pub('myView:viewId:view:loaded', 'myView');

Add a 'subscriptions' property to your view. The subscriptions property must be an hash as {channel:method}, where method is either a string representing a view method, or a function. The methods will be called with the view context.

var View = Backbone.View.extend({
  subscriptions: {
    'view:id:item:select': 'enable', // calls this.enable
    'view:id:item:select': function(){...}
  }
});

The subscriptions are tied with the delegateEvents/undelegateEvents methods. Calling delegateEvents() automatically sets subscriptions and calling undelegateEvents() unsets them.

Backbone Mediator does not impose many restrictions on how channels are named, but it's usually a good ideia to always follow the same pattern throghout your application. There are, however, a few simple rules you must follow in order to assure proper functioning:

1. dots(.) and colons(:) are used in channel namespacing to separate components.
2. All channels should have the same number of components
3. asterisk(*) is used for wildcards (see below)

These rules are specially important if you want to use wildcard channel subscription (see below)

Backbone Mediator suggests using a 4 namespaced component channel with the following pattern:

<className>:<objectID>:<item>:<event>

example:

albumModel:albumModel_id:artist:changed

albumView:albumView_id:view:loaded

albumView:button_DOM_id:button:click

Wilcards enable a controller to subscribe to a group of related channels without needing to subscribe to each one individually. This adds flexibility to your application.

Take the following example channels:

1. foo:bar:baz
2. foo:banana:baz
3. car:banana:baz

Subscribe to channel 1 and 2

Backbone.Mediator.sub('foo:*:baz', callback);

Subscribe to channel 2 and 3

Backbone.Mediator.sub('*:banana:baz', callback);

###Multiple wildcards

Multiple wilcards are allowed.

Subscribe to all channels started by foo

Backbone.Mediator.sub('foo:*:*', callback);

Subscribe to all channels ended in baz

Backbone.Mediator.sub('*:*:baz', callback);

Subscribe to all channels

Backbone.Mediator.sub('*:*:*', callback);

Please note that wildcards cannot be used when publishing, only when subscribing.

This means:

//Invalid
Backbone.Mediator.publish('myView:*:view:loaded', 'myView');

//Valid
Backbone.Mediator.subscribe('myView:*:view:loaded', 'myView');