QRCompositereport how?

var
  aMeta: TMetaFile;
  PageNum: Integer;
begin
  WPPDFPrinter1.FileName := 'C:\DEMO.PDF';
  FCount := 0;
  try
    Quickreport1.Visible := FALSE;
    WPPDFPrinter1.CanvasReference := wprefScreen;
    WPPDFPrinter1.BeginDoc;
    Quickreport1.Prepare;
    for PageNum := 1 to Quickreport1.QRPrinter.PageCount do
    begin
      WPPDFPrinter1.StartPage(Quickreport1.QRPrinter.PaperWidthValue,
          Quickreport1.QRPrinter.PaperLengthValue,254,254, 0);
      aMeta := Quickreport1.QRPrinter.GetPage(PageNum);
      try
       WPPDFPrinter1.DrawMetafileEx(0,0,0,0,aMeta.Handle,
         Screen.PixelsPerInch, Screen.PixelsPerInch );
      finally
        aMeta.Free;
        WPPDFPrinter1.EndPage;
      end;  
    end;
    WPPDFPrinter1.EndDoc;
    Quickreport1.QRPrinter.Free;
    Quickreport1.QRPrinter := nil;
  finally
    Quickreport1.Visible := TRUE;
  end;
end;