Class: Wee::Snapshot

Inherits:
Object show all
Defined in:
lib/wee/core/snapshot.rb

Overview

This class is for backtracking the state of components (or decorations/presenters). Components that want an undo-facility to be implemented (triggered for example by a browsers back-button), have to overwrite the Component#backtrack_state method. Class Wee::Snapshot simply represents a collection of objects from which snapshots were taken via methods take_snapshot.

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Snapshot

Returns a new instance of Snapshot.



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# File 'lib/wee/core/snapshot.rb', line 9

def initialize
  @objects = Hash.new
end

Instance Method Details

#add(object) ⇒ Object 



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# File 'lib/wee/core/snapshot.rb', line 13

def add(object)
  oid = object.object_id
  @objects[oid] = [object, object.take_snapshot] unless @objects.include?(oid) 
end

#restore ⇒ Object 



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# File 'lib/wee/core/snapshot.rb', line 18

def restore
  @objects.each_value { |object, value| object.restore_snapshot(value) }
end