Module: IronNails::Core::Observable

Included in:
IronNails::Controller::Base, View::Command, View::View, View::XamlProxy
Defined in:
lib/ironnails/observable.rb

Instance Method Summary collapse

Instance Method Details

#add_observer(event, &observer) ⇒ Object

Add observer as an observer on this object. observer will now receive notifications. observer is interest in the specified event



14
15
16
17
18
19
20
 
# File 'lib/ironnails/observable.rb', line 14

def add_observer(event, &observer)
  @observers = [] unless defined? @observers
  unless observer.respond_to? :call
    raise NoMethodError, "observer needs to respond to 'update'"
  end
  @observers << { :event => event, :observer => observer }
end

#count_observers ⇒ Object

Return the number of observers associated with this object.



41
42
43
44
45
46
47
 
# File 'lib/ironnails/observable.rb', line 41

def count_observers
  if defined? @observers
    @observers.size
  else
    0
  end
end

#delete_observer(event, &observer) ⇒ Object

Delete observer as an observer on this object. It will no longer receive notifications of the specified event.



26
27
28
29
 
# File 'lib/ironnails/observable.rb', line 26

def delete_observer(event, &observer)
  evt = { :event => event, :observer => observer }
  @observers.delete evt if defined? @observers
end

#delete_observers ⇒ Object

Delete all observers associated with this object.



34
35
36
 
# File 'lib/ironnails/observable.rb', line 34

def delete_observers
  @observers.clear if defined? @observers
end

#notify_observers(event, sender, *args) ⇒ Object

Notifies the registered observers that some interesting event has occurred. It will notify the interested parties by calling the block and passing it some context



54
55
56
 
# File 'lib/ironnails/observable.rb', line 54

def notify_observers(event, sender, *args)
  @observers.select {|evt| evt[:event] == event }.each {|evt| evt[:observer].call sender, *args } unless count_observers.zero?
end