event handler sample.rb

require 'rubygame'
include Rubygame
include Rubygame::EventTriggers

# Factory method to create KeyReleaseTriggers easily.
def released( key )
  return KeyReleaseTrigger.new( key )
end


class PlayerShip
  include EventHandler::HasEventHandler

  def initialize( input_manager )

    # Add hooks to the player ship's event handler. :up gets magically changed to
    # a KeyPressTrigger, and :start_moving_forward gets changed to a MethodAction.
    # So, the method gets called when the event is passed to the palyer ship's #handle method.
    make_magic_hooks(
      :up           => :start_moving_forward,
      released(:up) => :stop_moving_forward
      # etc.
    )

    # Register to receive KeyPressed and KeyReleased events.
    # You could wrap this in a #register method in input_manager, if you wanted.
    input_manager.append_hook(
      :owner   => self,
      :trigger => OrTrigger.new( KeyPressTrigger.new, 
                                 KeyReleaseTrigger.new ),
      # pass the events to player ship's #handle method, to be handled by the event handler
      :action  => MethodAction.new( :handle )
    )

  end

  def start_moving_forward( event )
    # MethodAction works with methods that take one arg (the event) or zero args,
    # like stop_moving_forward below. It's up to you, if you need more info from
    # the event or not.
    self.moving_forward = true
  end

  def stop_moving_forward
    self.moving_forward = false
  end

end