content: Sub Main()
      app = CreateObject("roAppManager")
      port=CreateObject("roMessagePort")
      screen = CreateObject("roPosterScreen")
      screen.SetMessagePort(port)
      screen.SetListStyle("arced-landscape")
      showOptions = [        
          {
              ShortDescriptionLine1:"BUY",
              ShortDescriptionLine2:"Purchase subscription"
          }
      ]
      screen.SetContentList(showOptions)
      screen.Show()
      
      while true
          msg = wait(0, screen.GetMessagePort())
          if type(msg) = "roPosterScreenEvent" then
              if msg.isListItemSelected() then
                  if msg.GetIndex() = 0 then 
                     showPurchaseScreen()
                  end if
              else if msg.isScreenClosed() then
                  return
              end if
          end If
      end while 
  End Sub