method

add_observer

v1_9_3_392 - Show latest stable - Class: Observable

add_observer(observer, func=:update)

public

Add observer as an observer on this object. so that it will receive notifications.

observer

the object that will be notified of changes.

func

Symbol naming the method that will be called when this Observable has changes.

This method must return true for observer.respond_to? and will receive *arg when #notify_observers is called, where *arg is the value passed to #notify_observers by this Observable

# File lib/observer.rb, line 126
  def add_observer(observer, func=:update)
    @observer_peers = {} unless defined? @observer_peers
    unless observer.respond_to? func
      raise NoMethodError, "observer does not respond to `#{func.to_s}'"
    end
    @observer_peers[observer] = func
  end

add_observer

Related methods