PrintPreview and grayscale

[KnotATypo]

Just ran into a problem. Have a page set up that uses Times New Roman font, some of the text is colored clBlue, some clGray, also have a small graphic that uses clGray, other graphics (lines) are all clBlack.

Preview is fine, printing to a Xerox printer is fine (every thing gets grayscaled), but printing to a HP printer only the text and graphics that are clBlack get printed, any other color is not printed at all. This printer does print in grayscale.

Ideas, fixes?

TIA

[Kambiz]

I guess you should update your HP printer's driver.

[KnotATypo]

That would have been my first guess, except that printing other graphics to this printer (with the same computer) does print the colors grayscaled correctly.

This is my code in a nutshell...

Code: Select all

//the main form
procedure TForm1.OnCreatePages(Sender: TPrintPreview);
begin
  Sender.GetPrinterOptions;
  Sender.BeginDoc;

  //...

  Sender.EndDoc;
end;

//the form that shows the preview
procedure TPrintPreviewDlg.PrintBtnClick(Sender: TObject);
var
  dlg : TSimplePrintDlg;
  mr : TModalResult;
begin
  //simple printing dialog
  dlg := TSimplePrintDlg.Create(Self);
  try
    dlg.Pages := PrintPreview1.TotalPages;
    dlg.PagesRBtn.Enabled := PrintPreview1.TotalPages > 1;

    mr := dlg.ShowModal;
    if mr = mrOk then begin
      Update;

      if dlg.AllRBtn.Checked then
        PrintPreview1.Print
      else
        PrintPreview1.PrintPages(dlg.PagesFromTo.X, dlg.PagesFromTo.Y);
    end else
      //if printer properties were changed (printer, orientation...)
      if mr = mrRetry then begin
        //main form OnCreatePages()
        if Assigned(FOnCreatePages) then
          FOnCreatePages(PrintPreview1);
      end;

  finally
    dlg.Free;
  end;
end;


[Kambiz]

As you said, on some printers the colored text (except RTF) is not printed at all. But, there's no problem for images.

Fortunately I could find a workaround for this issue. The folowing lines of code should be called before drawing the text.

Code: Select all

SetBkColor(Canvas.Handle, RGB(255, 255, 255));
SetBkMode(Canvas.Handle, TRANSPARENT);

It's clear that the bug is inside the printer driver.

Cheers

[KnotATypo]

Thanks,
Chris