The TTMSFNCGanttChartPrintIO component only seems to work with a PDF printer driver

FNC TMS FNC Gantt Chart
1

Hello,

I've installed the latest version of TMSFNCGanttChart. Now I wanted to work with the TTMSFNCGanttChartPrintIO component.
Unfortunately, both in TMS’s own “UPrintDemo” and in my own projects, printing only works on a single (virtual) printer, namely the Microsoft to PDF Printer. Any attempts to send print jobs from multiple computers to different physical printers always fail with the message that "" [blank] cannot be printed. The print job always ends up in the print manager with an error message. Could "" perhaps be a clue as to what the problem is?

One more note:
Sometimes, when the demo starts, a message appears stating that it is waiting for a connection to the (default) printer. The main window does not appear until after that. It does not seem to make any difference whether the (Windows?) message appears or not. (All other programs print without any problems.)

Thank you in advance for any suggestions.
PS: The TTMSFNCGanttChartPDFIO component seems to be working perfectly.

2

Thank you for letting us know, we will look into this as soon as possible.

3

I've tried to reproduce this issue in both FMX and VCL on different systems, but in all cases the printing worked as expected.

To help us investigate further, could you provide a bit more information?

As a first step, could you check whether printing works correctly using the standard VCL printing functionality on the same system? This will help us determine whether the issue is specific to our component or related to the printer or printer driver.

4

Thank you very much for your feedback.

Your suggestion regarding the standard VCL Printing System led to the solution:
The VCL Printing System generally works, but only if a valid value is set for "Printer.Title."

This does NOT work:
Printer.BeginDoc;
try
Printer.Title := 'VCL'; //or without this line
(…)
finally
Printer.EndDoc;
end;

This works:
Printer.Title := 'VCL';
Printer.BeginDoc;
try
(…)
finally
Printer.EndDoc;
end;

The trick was this one line, and now it prints:
if PrinterSetupDialog.Execute then
begin
Printer.Title := 'TMS Print'; //!!!
TMSFNCGanttChartPrintIO.Print;
end;

This appears to be purely an HP printer driver issue, since printing failed on all HP printers on different locations.