USB barcode reader in Qt4

Question

Hi.

I was wondering how could I integrate a USB barcode scanner into a Qt application, as well as a barcode printer.

I looked for tutorials but didn't find anything interesting out there. Any ideas?

Thanks in advance.

Answer 1

Most barcode scanners, IIRC basically work like a keyboard from the point of view of your application. You just provide a text field and the barcode reader "types" what it reads. So you don't really need to worry about that, other than validating the input and maybe providing a hidden text field if you don't want the input shown.

Or a modal dialog saying "scan item" with focus on a hidden text area.

In terms of a barcode printer, if you know the standard to which you are outputting, you would do well creating an SVG or PDF and exporting to print. This way your app can handle print dimensions and so on.

You don't say what language you are using, so I can't find you a barcode writing library.

Answer 2

It's not really a Qt question.

Most scanners behave like aUSB keypad and just enter numbers as if you had typed them, otheriwse they will come with a library that you would use like any other.

Answer 3

This looks like an answer that is dependant on the functionality of the USB barcode scanner.

In my experience, which involved a USB barcode scanner, it simply scanned the barcode and sent it to the application as if the keystrokes for each digit in the barcode was simulated. I didn't need to have an API library, I just place an input on the textbox awaiting for the next scan.

You should check and see if that is the case. Or there could be a specialized API library to interact with the scanner.

I did use the OPOS toolkit which had a series of shims or thin wrappers for the .NET code, it was until I discovered that Microsoft had an integrated POS sdk libraries for the .NET framework here and here.

Hope this helps, Best regards, Tom.