zlib Komprimierung mit Fortschritt

[Luckie]

Ich habe folgende Komprimierungsroutine:

Delphi-Quellcode:

procedure TSave.CompressFiles(Files: TStrings; const Filename: string);
var
  infile, outfile: TFileStream;
  tmpFile: TStreamProgressAdapter;
  compr             : TCompressionStream;
  i, l              : Integer;
  s                 : string;
begin
  if Files.Count > 0 then
  begin
    outfile := TFileStream.Create(Filename, fmCreate);
    try
      { the number of files }
      l := Files.Count;
      outfile.Write(l, SizeOf(l));
      for i := 0 to Files.Count - 1 do
      begin
        //FPercentDone := (i * 100) div Files.Count;
        infile := TStreamProgressAdapter.Create(TFileStream.Create(Files[i], fmOpenRead));
        try
          infile.OnProgress := SetProgress;
          Synchronize(DoProgress);
          { the original filename }
          s := ExtractFilename(Files[i]);
          l := Length(s);
          outfile.Write(l, SizeOf(l));
          outfile.Write(s[1], l);
          { the original filesize }
          l := infile.Size;
          outfile.Write(l, SizeOf(l));
          { compress and store the file temporary}
          tmpFile := TFileStream.Create('tmp', fmCreate);
          compr := TCompressionStream.Create(clMax, tmpfile);
          try
            compr.CopyFrom(infile, l);
          finally
            compr.Free;
            tmpFile.Free;
          end;
          { append the compressed file to the destination file }
          tmpFile := TFileStream.Create('tmp', fmOpenRead);
          try
            outfile.CopyFrom(tmpFile, 0);
          finally
            tmpFile.Free;
          end;
        finally
          infile.Free;
        end;
      end;
    finally
      outfile.Free;
    end;
    DeleteFile('tmp');
  end;
end;

TStereamProgressAdapter ist eine Stream-Klasse die ein OnProgress Ereignis implementiert (Klasse im Anhang). Ein Beispiel, wie man sie anwendet:

Delphi-Quellcode:

procedure TForm1.Button1Click(Sender: TObject);
var
  SrcFile: TStreamProgressAdapter;
  DestFile: TFileStream;
  Filename: string;
begin
  if OpenDialog1.Execute then
  begin
    Filename := OpenDialog1.FileName;
    SrcFile := TStreamProgressAdapter.Create(TFileStream.Create(FileName,
      fmOpenRead or fmShareDenyNone));
    try
      SrcFile.OnProgress := Progress;
      DestFile := TFileStream.Create(Filename + '.copy', fmCreate);
      try
        DestFile.CopyFrom(SrcFile, SrcFile.Size);
      finally
        DestFile.Free;
      end;
    finally
      SrcFile.Free;
    end;
  end;
end;

Jetzt hab eich aber ja nicht nur eine Quelldatei, sondern viele. Wie kann man es erreichen, dass man trotzdem den Fortschritt angezeigt bekommt?