I found two bugs inside the VCL, for the function InvalidateRow &
InvalidateCol. This error can not redisplay the visible cell in you grid.

The Original source code is
procedure TCustomGrid.InvalidateCol(ACol: Longint);
var
  Rect: TGridRect;
begin
  if not HandleAllocated then Exit;
  Rect.Top := 0;
  Rect.Left := ACol;
  Rect.Bottom := VisibleRowCount+1;
  Rect.Right := ACol;
  InvalidateRect(Rect);
end;

You must change it with
procedure TCustomGrid.InvalidateCol(ACol: Longint);
var
  Rect: TGridRect;
begin
  if not HandleAllocated then Exit;

  if FixedRows > 0 then
  begin
  Rect.Top := 0;
  Rect.Left := ACol;
  Rect.Bottom := FixedRows-1;
  Rect.Right := ACol;
  InvalidateRect(Rect);
 end

  Rect.Top := TopRow;
  Rect.Left := ACol;
  Rect.Bottom := TopRow+VisibleRowCount+1;
  Rect.Right := ACol;
  InvalidateRect(Rect);
end;

Original Source Code is
procedure TCustomGrid.InvalidateRow(ARow: Longint);
var
  Rect: TGridRect;
begin
  if not HandleAllocated then Exit;
  Rect.Top := ARow;
  Rect.Left := 0;
  Rect.Bottom := ARow;
  Rect.Right := VisibleColCount+1;
  InvalidateRect(Rect);
end;

You must change it with
procedure TCustomGrid.InvalidateRow(ARow: Longint);
var
  Rect: TGridRect;
begin
  if not HandleAllocated then Exit;

  if FixedCols > 0 then
  begin
  Rect.Top := ARow;
  Rect.Left := 0;
  Rect.Bottom := ARow;
  Rect.Right := FixedCols-1;
  InvalidateRect(Rect);
  end;

  Rect.Top := ARow;
  Rect.Left := LeftCol;
  Rect.Bottom := ARow;
  Rect.Right := LeftCol+VisibleColCount+1;
  InvalidateRect(Rect);
end;

It will be great that the VCL include a patch for that.

Cheers
Emmanuel

Please report your bug to

http://pso.inprise.com/webcustomer/clearexx_cgi/x_Select_Part_Bug.htm

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