Author: Tomas Rutkauskas

How to fix the incorrect painting of an ActiveX control, which occurs when a web 
page is scrolled

Answer:

In Delphi 4, when an ActiveForm is larger than the browser window the control is on 
top of IE's scroll bars. In Delphi 5 they changed the code to fix this but didn't 
get it quite right resulting in the painting problem when scrolling. You need to 
edit the Delphi 5 AxCtrls unit as follows:


1   function TActiveXControl.SetObjectRects(const rcPosRect: TRect;
2     const rcClipRect: TRect): HResult;
3   var
4     WinRect: TRect;
5   begin
6     try
7       IntersectRect(WinRect, rcPosRect, rcClipRect);
8       {BEGIN FIX}
9       WinRect := Bounds(rcPosRect.left, rcPosRect.Top, WinRect.Right - WinRect.Left +
10        rcClipRect.Left - rcPosRect.Left, WinRect.Bottom - WinRect.Top +
11        rcClipRect.Top - rcPosRect.Top);
12      {END FIX}
13      FWinControl.BoundsRect := WinRect;
14      Result := S_OK;
15    except
16      Result := HandleException;
17    end;
18  end;