Android Question To Print label with QR Code, using a barcode printer, from a b4a app

if the printer can be configured as a network printer, you
can connect to it from your app over a socket. you will,
however, have to learn to drive it. that is, you will have to
obtain the printer's documentation and learn how to issue
commands (to print) and receive responses (status
reports). you could also search the internet for software
allowing an android device to drive a network-connected
printer of your make and model.

why you have to have the app handle the printing is beyond me;
it only adds another layer of complexity. just sayin'.

you should let the server (or the computer where the server
resides) handle the printing. the printer is already
connected to the server waiting there to print for you. even if you
configure the printer to be a network printer, the printing should
be handled by the server (the printer drivers are already installed
or are available for installation from a cd).

the only benefit to having the app perform the printing would
be if a printer driver already existed for the android device
and/or if it was actually impossible for the server to print the
label/qr code (in which case, you might have to write the
driver yourself).

printing from an android device normally involves a wifi- or
bluetooth-enabled printer, for which there is often manufacturer's
support. you could purchase one if you had to print from the app.
(the manufacturer might even have an app ready to run, like HP
and Epson do for their printers). some members have managed
to print to serial printers from android devices. you can read about
their travails here.