How to stop the automatic scrolling of a Memo control?

Question

In Windows 7, a memo control (TMemo) will scroll automatically after text is insterted (Memo.Lines.Add(Path);), which I do not want, because scrolling is done by myself.

How can I stop the automatic scrolling?

Providential

When the memo scrolls automatically? – Emyle

when data is inserted. code: lstFiles.Lines.Add(Path);. lstFiles is TMemo. – Providential

Answer 1

Normally, adding text to a memo control scrolls the memo to the bottom of the inserted text. To prevent that, call Lines.BeginUpdate before adding text, and call EndUpdate afterwards:

procedure TForm1.Button1Click(Sender: TObject);
begin
  Memo1.Lines.BeginUpdate;
  try
    Memo1.Lines.Add('...');
    Memo1.Lines.Add('...');
    ...
  finally
    Memo1.Lines.EndUpdate;
  end;
end;

Scrubber

This functions OK but have undesired side effect of flickering :-(. Setting DoubleBuffered property is of no benefit. – Tolle

Can you explain why this works? In the documentation for System.Classes.TStrings.BeginUpdate it says "Some descendants of TStrings use this information to perform certain actions, such as telling a control to repaint, when updates are complete." – Slink

@New Because TMemoStrings.SetUpdateState is implemented the way it is. – Scrubber