[Solved] QR codes & Receipt printer

[Petrus Vorster]

Hi All

I can use the Qr code component to print individual labels on a label printer or receipt printers.
What I now need to do it print a whole bunch of different QR codes on a receipt.

Its just a simple loop from a listbox but I have always used a command to set up a RECT to allow the placement of the barcode, bit this command seems to cause problems:

Code: Pascal  [Select][+][-]

1.  Barcodeqr1.PaintOnCanvas(printer.Canvas,myrect);  

The command works perfect if you print one receipt or one label , then do the printer.enddoc, then print a new receipt/label.

To do that in a loop i tried:

Code: Pascal  [Select][+][-]

1.  l:= 20;
2.   t:= 50;
3.     for i := 0 to ListBox1.Items.Count - 1 do
4.     begin
5.   w:=barcodeqr1.Width;
6.   h:=barcodeQR1.Height;
7.   myrect:=rect(l,t,w,h);
8.     Printer.BeginDoc;
9.     barcodeqr1.Text:=listbox1.Items[i];
10.     barcodeqr1.Scale:=5;
11.     Barcodeqr1.PaintOnCanvas(printer.Canvas,myrect);
12.     inc(t,100);
13.     end;
14.  
15.  printer.EndDoc;                

That causes an error of 'PRITER IS PRINTING' but it doesnt print.
It would seem that command cannot be put in a loop with the printer.

Anyone here perhaps knows how to correct that?

-Regards,
Peter

[Petrus Vorster]

Hmmm. Ive got my printer.begindoc inside the loop.

[Petrus Vorster]

Now i have access violation errors... 

Anyone with ideas will be most welcome!

-Peter

[jcmontherock]

There is an example for business card:

https://forum.lazarus.freepascal.org/index.php/topic,64699.0.html

[Petrus Vorster]

HI

Thank you. I will need to study that.
I also notice the Qr.free which I did not do.

I need to change the data in the QR with every new QR code being printed on a receipt printer.
Its a list of tracking numbers I used to output with Code39 barcodes.
Then i changed to code128B with Lazreport which makes it very easy to print.
Unfortunately Lazreport Barcode items does not support QR codes.

The Qr codes can take more data, so I need to venture in that direction....

Thanks for the example.

-Peter

[paweld]

https://forum.lazarus.freepascal.org/index.php/topic,72561.msg568324.html#msg568324