MQL5 ReferenceStandard LibraryPanels and DialogsCRadioGroupOnScrollLineUp CreateOnEventAddItemValueCreateButtonOnVScrollShowOnVScrollHideOnScrollLineDownOnScrollLineUpOnChangeItemRedrawRowStateSelect OnScrollLineUp The virtual handler of the dependent VScroll (vertical scroll) control "ScrollLineUp" internal event. virtual bool OnScrollLineUp() Return Value true - event processed, otherwise - false. OnScrollLineDown OnChangeItem