Initial requestTechnology works but subsequent write attempts fail. Android 16, Samsung S24 ultra #802
Description
When launching the app and using requestTechnology(NfcV) on android, I get NfcV as a response from this code:
try {
const response = await NfcManager.requestTechnology(
[NfcTech.NfcV, NfcTech.Ndef],
{
alertMessage: systemPrompt,
}
)
also tested:
const response = await NfcManager.requestTechnology(NFC_TECH, {
alertMessage: systemPrompt,
isReaderModeEnabled: true,
readerModeDelay: 0,
readerModeFlags:
NfcAdapter.FLAG_READER_NFC_V |
NfcAdapter.FLAG_READER_SKIP_NDEF_CHECK |
NfcAdapter.FLAG_READER_NO_PLATFORM_SOUNDS,
})
And I open the session with:
await NfcManager.registerTagEvent({
isReaderModeEnabled: true, /* tested both with and without */
readerModeFlags:
NfcAdapter.FLAG_READER_NFC_V |
NfcAdapter.FLAG_READER_SKIP_NDEF_CHECK |
NfcAdapter.FLAG_READER_NO_PLATFORM_SOUNDS,
readerModeDelay: 0,
})
const response = await NfcManager.nfcVHandler.transceive(modifiedBytes)
I then run this in the finally, which runs fine with no error:
finally {
await NfcManager.cancelTechnologyRequest({ throwOnError: true })
}
but the next time I try to requestTechnology, I get null instead of NfcV (despite waiting 10s, removing the tag from scanning distance, etc). But I do get a log response from my native intent before the requestTechnology runs. My analysis of the situation is that the android background NFC reader somehow gains priority, even when we are actively attempting to write to the tag. When I attempt to open another session after it returns null, I get that I can only have one session open at a time, which implies that the previous session is closed and maybe cleared, although probably not correctly. Why could this be happening?
nativeIntent:
export async function redirectSystemPath({
path,
}: {
path: string
initial: boolean
}): Promise<Href | null> {
} else if (path.startsWith('https:// /* Tag content */ ')) {
const result = await parseNfcUrl(path)
console.log('parsed nfc url from redirectSystemPath')
}
return path as Href
}
Version: "react-native-nfc-manager": "^3.16.2", also surface level tested on 3.17.1 with the same issue
EDIT:
Appears to be related to the android manifest. If I strip away all forms of nfc discovery from the manifest then it becomes a whole lot more consistent and responsive:
'android.nfc.action.NDEF_DISCOVERED',
'android.nfc.action.TECH_DISCOVERED',
'android.nfc.action.TAG_DISCOVERED',
'android.intent.action.NDEF_DISCOVERED',
It is very possible that the error happens either earlier, during the opening of the session, or it might be something to do with the manifest configuration of this project. Or it might just be android behavior, which has to be disabled somehow.
Further debugging, I think this might be related to the state machine of the ISO15693/NfcV chip, it happens when a write is cancelled and im guessing the tag does not get enough power to finish the operations and go back to a writeable state. The issue resolves if I read it a couple of times and restart my app
Final edit:
It appears to be a bug with the samsung nfc service, workaround found here: