FXRuby - capture close on the main window

capture_close.rb

require 'fox16'
include Fox

class MyApp < FXMainWindow
  def initialize(app)
    @app = app
    super(app, "Test", :height => 150, :width => 350, :opts=> DECOR_ALL)
    self.connect(SEL_CLOSE, method(:on_close))
  end

  def create
    super
    show(PLACEMENT_SCREEN)
  end

  def on_close(sender, sel, event)
    q = FXMessageBox.question(@app, MBOX_YES_NO, "Sure?", "You sure?")
    if q == MBOX_CLICKED_YES
      return 0
    end
  end
end

FXApp.new do |app|
  MyApp.new(app)
  app.create
  app.run
end