content: sub main(params)
  
    screen = createObject("roSGscreen")
    port = createObject("roMessagePort")
    screen.setMessagePort(port)
  
    scene = screen.createScene("Main")
    screen.show() ' vscode_rale_tracker_entry
    scene.observeField("close",port)
  
    while true
        msg = wait(0,port)
        msgType = type(msg)
        if "roSGScreenEvent" = msgType
            if msgType.isScreenClose() then return
        else if "roSGNodeEvent" = msgType
          field = msg.getField()
          if field = "close" then return
        end if
    end while
  end sub