Basic printing of form content.

[MarkMLl]

I have a form containing a map viewer, a treeview and a couple of graphical panels.

As attached, I am able to dump a .png with no problems using the code below:

Code: Pascal  [Select][+][-]

1. procedure TFormMain.MenuViewOutputAsPngClick(Sender: TObject);
2.  
3. var
4.   defaultName: string;
5.   png: TPortableNetworkGraphic;
6.   everything: TRect;
7.  
8. begin
9.  
10. (* We want the default name to match what's currently on the status bar, if we  *)
11. (* used the current time this might differ by a few seconds from what's being   *)
12. (* displayed due to message backlog.                                            *)
13.  
14.   defaultName :=   StatusBar1.Panels[2].Text;
15.   if Pos('.', defaultName) > 0 then
16.     SetLength(defaultName, Pos('.', defaultName) - 1);
17.   defaultName := DelChars(defaultName, '-');
18.   defaultName := DelChars(defaultName, 'T');
19.   defaultName := DelChars(defaultName, ':');
20.  
21. (* Capture the image to match, do this before faffing around trying to get the  *)
22. (* name right in case it's an incident that needs to be recorded.               *)
23.  
24.   png := TPortableNetworkGraphic.Create;
25.   try
26.     everything.Top := 0;
27.     everything.Left := 0;
28.     everything.Bottom := Height - MainMenu1.Height - 2;
29.     everything.Right := Width - 1;
30.     png.Height := everything.Bottom + 1;
31.     png.Width := everything.Right + 1;
32.     png.Canvas.CopyRect(everything, Canvas, everything);
33.     SaveDialog1.Filename := AirfieldShortname + '-' + defaultName;
34.     SaveDialog1.DefaultExt := 'png';
35.     SaveDialog1.InitialDir := UserHome();
36.     if SaveDialog1.Execute then
37.       png.SaveToFile(SaveDialog1.Filename)
38.   finally
39.     png.Free
40.   end
41. end { TFormMain.MenuViewOutputAsPngClick } ;
42.  

Similar code works to the clipboard.

What do I have to do to instead send this to a printer? I've tried several variants of the code below:

Code: Pascal  [Select][+][-]

1. procedure TFormMain.MenuViewPrintClick(Sender: TObject);
2.  
3. const
4.   LEFTMARGIN = 100;
5.   HEADLINE = 'I Printed My Very First Text On ';
6. var
7.   YPos, LineHeight, VerticalMargin: Integer;
8.   SuccessString: String;
9.  
10. var
11.   everything: TRect;
12.  
13.   workingBitmap: TBitMap;
14.   fromLimits, toLimits: TRect;
15.  
16. begin
17.  
18. {
19.  
20. // This works.
21.  
22. // https://wiki.freepascal.org/Using_the_printer
23.   if PrintDialog1.Execute() then begin // This works
24.     with Printer do try
25.       BeginDoc;
26.       Canvas.Font.Name := 'Courier New';
27.       Canvas.Font.Size := 10;
28.       Canvas.Font.Color := clBlack;
29.       LineHeight := Round(1.2 * Abs(Canvas.TextHeight('I')));
30.       VerticalMargin := 4 * LineHeight;
31.       // There we go
32.       YPos := VerticalMargin;
33.       SuccessString := HEADLINE + DateTimeToStr(Now);
34.       Canvas.TextOut(LEFTMARGIN, YPos, SuccessString);
35.     finally
36.       EndDoc;
37.     end;
38.   end
39. }
40.  
41. // The best I can get from either of the below is a blank page.
42.  
43.   workingBitMap := TBitMap.Create;
44.   workingBitMap.Width := Width;
45.   workingBitMap.Height := Height - MainMenu1.Height;
46.   PaintTo(workingBitMap.Canvas, 0, 0);
47.   fromLimits := Rect(0, 0, workingBitMap.Width, workingBitMap.Height);
48.   toLimits := Rect(0, 0, Printer.PaperSize.Width, Printer.PaperSize.Height);
49.   if PrintDialog1.Execute() then begin
50.     Printer.BeginDoc;
51.     Printer.Canvas.CopyRect(toLimits, workingBitMap.Canvas, fromLimits);
52.     Printer.EndDoc;
53.     workingBitMap.Free
54.   end;
55.  
56. {
57. // https://forum.lazarus.freepascal.org/index.php/topic,62651.msg473978.html#msg473978
58.   if PrintDialog1.Execute() then begin // This doesn't work
59.     Printer.BeginDoc;
60.     try
61.       everything.Top := 0;
62.       everything.Left := 0;
63.       everything.Bottom := Min(Printer.PageHeight, Height - MainMenu1.Height) - 2;
64.       everything.Right := Min(Printer.PageWidth, Width) - 1;
65.       Printer.Canvas.CopyRect(everything, Canvas, everything)
66.     finally
67.       Printer.EndDoc
68.     end
69.   end
70. }
71. end { TFormMain.MenuViewPrintClick } ;
72.  

If nobody has any quick suggestions I'll drop this for the moment, since what I'm trying to focus on is generating a video for the airfield's "fly-in-" in three weeks time.

Lazarus 2.2.6, FPC 3.2.2, Linux with GTK2 on a KDE desktop (Debian 12), printer is a networked colour laser branded Dell which is generally trouble-free.

MarkMLl

[wp]

Why don't you just CopyRect the png that you successfully created in the 1st code to the printer's Canvas?

I am attaching a project which has a MapViewer and a button on a form, paints the form onto a bitmap and stretch-prints the bitmap to the printer such that it fits into the printable page width (raw page width minus page margins)

[MarkMLl]

Why don't you just CopyRect the png that you successfully created in the 1st code to the printer's Canvas?

I am attaching a project which has a MapViewer and a button on a form, paints the form onto a bitmap and stretch-prints the bitmap to the printer such that it fits into the printable page width (raw page width minus page margins)

Using your standalone demo, the image is correctly transferred to the test.bmp file but does not appear on either the colour or the B&W printer; I do however get the two lines of text.

Same happens if I move your code into my program (which I've done, because I know from other forum postings etc. that you've put substantial work into the scaling etc. right).

If you have any immediate suggestions I'll try them in the interest of understanding what's going wrong, but otherwise I'll just disable the menu entry until I've moved the whole thing onto Lazarus v3 or even v4 (which won't be for at least another month).

Thanks for the help, which if nothing else has narrowed the problem down to Lazarus v2.

MarkMLl

[wp]

For testing I had printed only to PDF, but now I switched to the "real" printer - perfect print-out, no issue. An issue with your printer driver? What happens when you print to PDF and/or a similar printer?

[MarkMLl]

For testing I had printed only to PDF, but now I switched to the "real" printer - perfect print-out, no issue. An issue with your printer driver? What happens when you print to PDF and/or a similar printer?

I've just installed Debian's printer-driver-cups-pdf, printing e.g. this page to a PDF works fine but your demo only outputs the two lines of text.

MarkMLl

[MarkMLl]

I've just installed Debian's printer-driver-cups-pdf, printing e.g. this page to a PDF works fine but your demo only outputs the two lines of text.

It's specific to GTK2, possibly on LCL v2 (the Lazarus v3.0 I've got here has an internal error on GTK2, so I've not been able to test that combination yet). QT5 works.

MarkMLl