Creating my first Mac app with MacRuby

Alarm.rb

#
#  AppDelegate.rb
#  Alarm
#
#  Created by Luis Gerhorst on 09.09.13.
#

class AppDelegate
	
	attr_accessor :window, :datePicker, :createAlarmButton, :deleteAlarmButton
	
	def applicationDidFinishLaunching(a_notification)
        
        	datePicker.setDateValue(NSDate.date)
        
	end
	
	def createAlarm(sender)
		
        	puts "creating..."
        
		@alarm = Alarm.new
		@alarm.timer(datePicker.dateValue)
		
	end
    
    	def deleteAlarm(sender)
        
        	puts "deleting..."
        
        	@alarm.delete
        	@alarm = nil
        
   	end
	
end

class Alarm
	
	def timer(date)
        
		@timer = NSTimer.scheduledTimerWithTimeInterval(1.0, target: self, selector: "fire:", userInfo: nil, repeats: true)
        	@timer.setFireDate(date)
        
        	puts "created"
        
	end
	
	def fire(userInfo)
        
		NSSound.soundNamed('Basso').play
        
        	puts "fired"
        
	end
    
    	def delete
        
        	@timer.invalidate
        	@timer = nil
        
        	puts "deleted"
        
   	end
	
end