Android Question NFC tag how to read the UID

[davemorris]

Hi, Guys
Just started a project to handle NFC tags - found Erel's tutorial on read/write NFC tags

NFC - Reading and Writing

NFC v2.00 adds support for low level access to the NFC features. This allows reading and writing from NFC tags. The NFC library provides three features: - Reading Ndef tags based intent filters: Reading NDEF data from NFC tags - Sending data between two devices (Android Beam)...

www.b4x.com

And it works great for the tags I am using, should be easy to adapt it to fit into my project.

However, I need to also read the tag's UID along with a small amount of tag data (the UID code is used as an encryption key to ensure the tag has not been tampered with or duplicated).


Question is: Is there a simple way to adapt Erel's code to read the UID along with some data from the tag?


I did find another post

Getting UID from an nfc-v tag (NFC2 lib)

Hello, I'm using the nfc2 library to handle nfc-v tags, calling runasync with transceive (and related byte payload). Is there a way to use the same system to retrieve the Unique Tag Id? As far as i know it should be visible after the _connected event, but i see no way to retrieve it. I'm...

www.b4x.com

but is did not give an detailed example on how to do it (I assume it was posted by someone who knows a lot more about using NFC technologies than me!)

Once again, grateful for any help

Dave Morris

 

[drgottjr]

post #5 from here: https://www.b4x.com/android/forum/threads/nfc-reading-and-writing.64451/
shows you how to do it

also, refer to this: https://developer.android.com/reference/android/nfc/Tag#getId()
there may be no tagid available.

also, the base example for your app only covers tags using NDEF technology

 

[davemorris]

Hi drgottjr

Thanks for the input, to be honest I only got as far with this post when the example worked. I do feel a bit of a idiot not reading posting below.

I will have a go at the suggestions in the posting, very sorry to post a question when the answer was a few posts lower down.

Thanks again for your help.
Dave