content: function main() as void
     port = createObject("roMessagePort")
     screen = createObject("roSGScreen")
     screen.setMessagePort(port)
  
     scene = screen.createScene("MainScene")
     scene.backgroundUri = ""
     scene.backgroundColor="#333333FF"
     screen.show()
  
     while true
        msg = wait(0, port)
        msgType = type(msg)
        if msgType = "roSGScreenEvent"
           if msg.isScreenClosed()
              return
           end if
        end if
     end while
  end function
  