Procedure WCB(WindowID, Message, wParam, lParam)
  Result = #PB_ProcessPureBasicEvents
  Select Message
   Case #WM_CTLCOLORSTATIC
      Select lparam
      Case GadgetID(1)
         SetBkMode_(wparam,#TRANSPARENT)
         ProcedureReturn GetStockObject_(#HOLLOW_BRUSH)
      EndSelect
  EndSelect
  ProcedureReturn Result
EndProcedure

If OpenWindow(0,0,0,500,250,"Window",#PB_Window_SystemMenu|#PB_Window_ScreenCentered)
  TextGadget(1,10,10,400,20,"Transparenter Text",0)
  
  SetWindowColor(0,RGB(255,255,0))
  SetWindowCallback(@WCB(),0)
Repeat : Until WaitWindowEvent() = #PB_Event_CloseWindow
EndIf