Procedure.l WindowCallback(Windowid,Message,wParam,lParam) Result = #PB_ProcessPureBasicEvents Select Message Case #WM_HELP *Helpinfo.HELPINFO = lParam Select *Helpinfo\iCtrlId Case 1 MessageRequester("","Hilfe-Text",0) EndSelect EndSelect ProcedureReturn Result EndProcedure If OpenWindow(0,0,0,500,250,"Window",#PB_Window_SystemMenu|#PB_Window_ScreenCentered) ButtonGadget(1,10,10,100,20,"Testbutton",0) SetWindowLongPtr_(WindowID(0),#GWL_EXSTYLE,#WS_EX_CONTEXTHELP) SendMessage_(WindowID(0),#WM_NCPAINT,1,0) SetWindowCallback(@WindowCallback()) Repeat : Until WaitWindowEvent() = #PB_Event_CloseWindow EndIf