delphiscrollbardelphi-10.1-berlintscrollbox

How to detect whether scrollbar is at the very bottom?

It is easy to detect whether the vertical scrollbar of a TScrollBox is at the very top or not:

IsScrollBarAtTop := ScrollBox1.VertScrollBar.Position = 0;

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But how can I detect whether the vertical scrollbar of a TScrollBox is at the very BOTTOM or not?

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Solution

  • You can retrieve scroll bar information through the API and determine if its at the bottom.

    function IsScrollBarAtBottom(Box: TScrollBox): Boolean;
var
  Info: TScrollInfo;
begin
  Info.cbSize := SizeOf(Info);
  Info.fMask := SIF_POS or SIF_RANGE or SIF_PAGE;
  Win32Check(GetScrollInfo(Box.Handle, SB_VERT, Info));
  Result := Info.nPos >=  Info.nMax - Info.nMin - Info.nPage;
end;