Using handheld QR Code scanner to launch program & perform action

Question

I may be grasping for the moon here, but this is my goal. I have an MIS program for our jobs and we are looking to use a scanner to scan the job ticket and launch the program.

I don't know very much about Python or program coding. My background is web dev, but I learn fast and really, coding is coding. Different types simply have different rules/languages for going "if this then do this". I know it's more complex than that, but that's the simplified way of looking at it.

I came up with a solution here: Industrial Handheld QRCode Scanner Open URL in Browser that uses the web based version of the software, but that is not what the boss wants.

What he wants is this:

1. Scan barcode
2. Program auto launches (or goes to program if already open)
3. Auto opens specific area
4. Auto selects option from top menus
5. Auto enters data picked up from the scan into empty field
6. Auto hits "enter" to load specific job
7. Script resets back to "ready" waiting for next scan

All from scanning the one barcode with no other user interaction.

This will be running on Windows 7 machines. It looks like EvDev might be a good place to start (http://python-evdev.readthedocs.io/en/latest/tutorial.html) but it seems to only have Linux installers.

If someone can at least point in the rough direction, I can probably figure it out. I'm just not sure on how to limit the input to only inputs from the scanner then trigger the code to run, and also, on how to tell it to do certain things within the program.

Thank you for the help!

Answer 1

The first step is generating the QR codes for this you can use a number of libraries - my favourite for this is PyQrCode.

You can decode images using ZBar python bindings but currently there are no ready build binaries for Python 2.7 or 3.5 on pypi - this may change in the near future or you will have to build your own.

There is also a very good article here that covers using a webcam to detect & capture QR codes.

Once you have your QR code decoded you need to find & possibly start the application and transfer the data to it, if the application has an COM interface python can call it directly using comtypes if not there are still some mechanisms that can used.

For limiting the QR codes that it responds to you can use the convention already used for QR codes of prefixing the information with an action tag, e.g. phone numbers are normally prefixed tel:, etc. I would recommend using a similar syntax to to URLs to distinguish actions & fields, e.g. ourtag:anaction?f1=val1;f2=val2 - you can associate the action for ourtag with your program, anaction with which action to perform, f1, etc., would be field identifiers, etc., this is quite simple to parse and then apply.