Procedure.l MouseToGadget(GadgetID)
  hWnd.l
  If IsWindow_(GadgetID)
    hWnd=GadgetID
  ElseIf IsGadget(GadgetID)
    hWnd=GadgetID(GadgetID)
  Else
    ProcedureReturn #False
  EndIf
  GadgetRect.RECT
  GetWindowRect_(hWnd,@GadgetRect)
  ProcedureReturn SetCursorPos_((GadgetRect\left + GadgetRect\right) / 2,(GadgetRect\top + GadgetRect\bottom) / 2)
EndProcedure

If OpenWindow(0,0,0,500,250,"Window",#PB_Window_SystemMenu|#PB_Window_ScreenCentered)
  ButtonGadget(1,10,10,100,20,"Test-Button",0)
  
  MouseToGadget(1)
Repeat : Until WaitWindowEvent() = #PB_Event_CloseWindow
EndIf