Scrolling RichEdit without it having focus

Question

I need to scroll a RichEdit to the very end after a line is added. I have this RichEdit in a separate form, that I don't want to get focus at all. I tried often suggested solution:

RichEdit.Lines.Add(someText);
RichEdit.SelStart:=RichEdit.GetTextLen;
SendMessage(RichEdit.handle, EM_SCROLLCARET, 0, 0);

But this doesn't work for me. However, when I focus the RichEdit before calling the SendMessage using RichEdit.SetFocus; it works just fine. That, however, ruins my other needs for the app.

I'm using XE2. Thanks

Tatiana

Answer 1

This is what I do:

SendMessage(RichEdit.Handle, WM_VSCROLL, SB_BOTTOM, 0);

Nonreturnable

FWIW, that works to jump at the end, wherever the caret might be. However to jump at the current position of the caret, you have to do the HideSelection trick. – Hasty

Answer 2

See this blog post by François Gaillard: richedit-on-scrolling-strike.

Appearently a bug, here is the workaround solution :

procedure ScrollToEnd(ARichEdit: TRichEdit);
var
  isSelectionHidden: Boolean;
begin
  with ARichEdit do
  begin
    SelStart := Perform( EM_LINEINDEX, Lines.Count, 0);//Set caret at end
    isSelectionHidden := HideSelection;
    try
      HideSelection := False;
      Perform( EM_SCROLLCARET, 0, 0);  // Scroll to caret
    finally
      HideSelection := isSelectionHidden;
    end;
  end;
end;

Robenarobenia