Nanoc3::NotificationCenter provides a way to send notifications between objects. It allows blocks associated with a certain notification name to be registered; these blocks will be called when the notification with the given name is posted.

It is a slightly different implementation of the Observer pattern; the table of subscribers is not stored in the observable object itself, but in the notification center.

Public Visibility

Public Class Method Summary

on(name, id = nil, &block)	Adds the given block to the list of blocks that should be called when the notification with the given name is received.
post(name, *args)	Posts a notification with the given name.
remove(name, id)	Removes the block with the given identifier from the list of blocks that should be called when the notification with the given name is posted.

Public Class Method Details

on

public on(name, id = nil, &block)

Adds the given block to the list of blocks that should be called when the notification with the given name is received.

`name`:	The name of the notification that will be posted.
`id`:	An identifier for the block. This is only used to be able to remove the block (using the remove method) later. Defaults to nil.

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          # File 'lib/nanoc3/base/notification_center.rb', line 25

def on(name, id=nil, &block)
  initialize_if_necessary(name)

  # Add observer
  @notifications[name] << { :id => id, :block => block }
end

post

public post(name, *args)

Posts a notification with the given name. All arguments wil be passed to the blocks handling the notification.

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          # File 'lib/nanoc3/base/notification_center.rb', line 34

def post(name, *args)
  initialize_if_necessary(name)

  # Notify all observers
  @notifications[name].each do |observer|
    observer[:block].call(*args)
  end
end

remove

public remove(name, id)

Removes the block with the given identifier from the list of blocks that should be called when the notification with the given name is posted.

`name`:	The name of the notification that will be posted.
`id`:	The identifier of the block that should be removed.

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          # File 'lib/nanoc3/base/notification_center.rb', line 50

def remove(name, id)
  initialize_if_necessary(name)

  # Remove relevant observers
  @notifications[name].reject! { |i| i[:id] == id }
end

Class: Nanoc3::NotificationCenter

Public Visibility

Public Class Method Summary

Public Class Method Details

on

post

remove