Issue with NfcManager.requestTechnology(NfcTech.Ndef) and Expo

[TheKeenestKeen]

Hi @whitedogg13. I purchased your course yesterday and I am able to follow everything step for step until I reach the following line

await NfcManager.requestTechnology(NfcTech.Ndef)

which throws this error:

at http://192.168.88.35:8081/node_modules/expo/AppEntry.bundle?platform=ios&dev=true&hot=false&minify=false:545956:321 in _createSuperInternal at http://192.168.88.35:8081/node_modules/expo/AppEntry.bundle?platform=ios&dev=true&hot=false&minify=false:545967:25 in NfcErrorBase at http://192.168.88.35:8081/node_modules/expo/AppEntry.bundle?platform=ios&dev=true&hot=false&minify=false:545956:321 in _createSuperInternal at http://192.168.88.35:8081/node_modules/expo/AppEntry.bundle?platform=ios&dev=true&hot=false&minify=false:545997:26 in SecurityViolation at node_modules/react-native-nfc-manager/src/NfcError.js:103:15 in buildNfcExceptionIOS at http://192.168.88.35:8081/node_modules/expo/AppEntry.bundle?platform=ios&dev=true&hot=false&minify=false:546461:38 in handleNativeException$

I am however able to get a read using

NfcManager.setEventListener(NfcEvents.DiscoverTag, (tag: any) => {
    ...
})

However, the eventlistener approach above only allows for reading and not writing. What is causing this issue with the requestTechnology method above?

For context, I am using Expo with the Development Client build with react-native-nfc-manager as a plugin.

[whitedogg13]

Hi @TheKeenestKeen thanks for supporting!

The error you mentioned is an exception from iOS: tagResponseError (which means the actuall error happens in the NFC tag itself, but reported by iOS), and I think using Expo should be just fine.

Please check:

• what tag do you use?
• has the tag been formatted to NDEF yet?

BTW, the course has its own discord channel nfcs-with-react-native (in newline's discord server), or you're also welcome to send me DM via Twitter, mine handle is @richie13tw, I will be both places to help!

[TheKeenestKeen]

Hi @whitedogg13 glad to support!

I can write into the tag successfully using your NFC App on the Appstore. For instance, this is text payload I just wrote: "hello there world".

This is the response object I got using event listener approach from my App: Tag found, Object { "ndefMessage": Array [ Object { "id": Array [], "payload": Array [ 2, 101, 110, 104, 101, 108, 108, 111, 32, 116, 104, 101, 114, 101, 32, 119, 111, 114, 108, 100, ], "tnf": 1, "type": Array [ 84, ], }, ], }

However, even with this correctly formatted NDEF, the

await NfcManager.requestTechnology(NfcTech.Ndef)

approach still shows the exception detailed in my first post.

As for the tag I am using, here is some info:

ST25TA512B, ST25TA02KB ST25TA02KB‑D, ST25TA02KB‑P Datasheet

• NFC Forum Type 4 Tag IC with up to 2-Kbit EEPROM
• ISO/IEC 14443 Type A
• Support NDEF data structure

[whitedogg13]

Hi @TheKeenestKeen you're using the NFC type 4 tags.

NFC type 4 (IsoDep) tags have different behavior from tag 2 (NfcA) tags, which are used in our course as demo.

In order to enable NDEF support for type 4 tags, you will have extra setup to do. You will need to update Info.plist with com.apple.developer.nfc.readersession.iso7816.select-identifiers:

        <key>com.apple.developer.nfc.readersession.iso7816.select-identifiers</key>
    <array>
        <string>D2760000850100</string>
        <string>D2760000850101</string>
    </array>

The full example can be found in our open source app here, then it should work!

[TheKeenestKeen]

Thanks so much @whitedogg13. That did the trick. Thanks for bearing through with my confusion. And thanks for creating react-native-nfc-manager.

[whitedogg13]

@TheKeenestKeen my pleasure!

[nfuenmamelt]

@TheKeenestKeen how do you solve this? was the TAG?