Method: Mongoid::StateMachine::ClassMethods#event

Defined in:

lib/mongoid/state_machine.rb

#event(event, opts = {}, &block) ⇒ Object

Define an event. This takes a block which describes all valid transitions for this event.

Example:

class Order

acts_as_state_machine :initial => :open

state :open
state :closed

event :close_order do
  transitions :to => :closed, :from => :open
end

end

transitions takes a hash where :to is the state to transition to and :from is a state (or Array of states) from which this event can be fired.

This creates an instance method used for firing the event. The method created is the name of the event followed by an exclamation point (!). Example: order.close_order!.

# File 'lib/mongoid/state_machine.rb', line 203

def event(event, opts={}, &block)
  tt = read_inheritable_attribute(:transition_table)

  e = SupportingClasses::Event.new(event, opts, tt, &block)
  write_inheritable_hash(:event_table, event.to_sym => e)
  define_method("#{event.to_s}!") { e.fire(self) }
end