content: sub main()
    m.port = CreateObject("roMessagePort")
  	screen = CreateObject("roSgScreen")
  	screen.setMessagePort(m.port)
  	scene = screen.createScene("demo")
  	screen.show()
  
  	while(true)
  		msg = wait(0, m.port)
  		msgType = type(msg)
  		if msgType = "roSgScreenEvent"
  			if msg.isScreenClosed() then return
  		end if
    end while
  end sub
  