Android SDK: NFC data listener

This feature needs to be enabled for your integration.

Contact your solutions engineer for info and configuration.

Starting with Android SDK version 7.15.0, you can receive real-time callbacks when the SDK successfully reads or fails to read NFC data from identity documents. This allows your app to get access to extracted NFC data (DG1 and DG2) for additional processing or analytics.

Use the NFC data listener when you need to:

• Access raw NFC data (Machine Readable Zone and Face Image) for additional verification

• Track NFC reading success/failure for analytics

• Implement custom handling based on NFC scan results

• Store NFC data in your own systems for compliance or audit purposes

Prerequisites

The listener will only receive callbacks if:

• NFC reading has been enabled for your  integration by Veriff

• NFC reading permissions have been granted in the SDK

• The end-user's document supports NFC (e-passports, some ID cards)

• The device has NFC hardware capability

Add NFC data listener

Step 1: Implement the listener interface

Create a class that implements VeriffNfcDataListener:

import com.veriff.VeriffNfcDataListener
import com.veriff.NfcData
import android.util.Log

class MyNfcDataListener : VeriffNfcDataListener {
    
    override fun onNfcDataExtracted(nfcData: NfcData) {
        // Called when NFC reading succeeds
        Log.d("NFC", "DG1: ${nfcData.dg1}")
        Log.d("NFC", "DG2: ${nfcData.dg2}")
        
        // Process the NFC data as needed
        // Both dg1 and dg2 are Base64-encoded strings
    }
    
    override fun onNfcDataExtractionFailed() {
        // Called when NFC reading fails
        Log.w("NFC", "Failed to extract NFC data")
        
        // Handle failure case
    }
}

import com.veriff.VeriffNfcDataListener;
import com.veriff.NfcData;
import android.util.Log;
import org.jetbrains.annotations.NotNull;

public class MyNfcDataListener implements VeriffNfcDataListener {
    
    @Override
    public void onNfcDataExtracted(@NotNull NfcData nfcData) {
        // Called when NFC reading succeeds
        Log.d("NFC", "DG1: " + nfcData.getDg1());
        Log.d("NFC", "DG2: " + nfcData.getDg2());
        
        // Process the NFC data as needed
        // Both dg1 and dg2 are Base64-encoded strings
    }
    
    @Override
    public void onNfcDataExtractionFailed() {
        // Called when NFC reading fails
        Log.w("NFC", "Failed to extract NFC data");
        
        // Handle failure case
    }
}

Step 2: register the listener in configuration

Add the listener to your Veriff Configuration when starting the SDK:

val configuration = Configuration.Builder()
    .veriffNfcDataListener(MyNfcDataListener())
    .build()

val intent = Sdk.createLaunchIntent(this, sessionUrl, configuration)
startActivityForResult(intent, REQUEST_CODE_VERIFF)

Configuration configuration = new Configuration.Builder()

    .veriffNfcDataListener(new MyNfcDataListener())
    .build(); (edited)
Intent intent = Sdk.createLaunchIntent(this, sessionUrl, configuration);
startActivityForResult(intent, REQUEST_CODE_VERIFF);

import java.util.Base64
override fun onNfcDataExtracted(nfcData: NfcData) {
    // Decode DG1 (Machine Readable Zone)
    nfcData.dg1?.let { dg1Base64 ->
        val dg1Bytes = Base64.getDecoder().decode(dg1Base64)
        // Process DG1 binary data
    }

    // Decode DG2 (Face Image)
    nfcData.dg2?.let { dg2Base64 ->
        val dg2Bytes = Base64.getDecoder().decode(dg2Base64)
        // dg2Bytes contains JPEG2000 encoded face image
        // You can save this as a file or process it further
    }
}

import java.util.Base64;
@Override
public void onNfcDataExtracted(@NotNull NfcData nfcData) {
    // Decode DG1 (Machine Readable Zone)
    if (nfcData.getDg1() != null) {
        byte[] dg1Bytes = Base64.getDecoder().decode(nfcData.getDg1());
        // Process DG1 binary data
    }

    // Decode DG2 (Face Image)
    if (nfcData.getDg2() != null) {
        byte[] dg2Bytes = Base64.getDecoder().decode(nfcData.getDg2());
        // dg2Bytes contains JPEG2000 encoded face image
        // You can save this as a file or process it further
    }
}

Decoding Errors

You may get errors when decoding Base64 due to:

• Invalid Base64: ensure you are using java.util.Base64, not other Base64 implementations

• Character encoding: do not try to decode as UTF-8 string directly, DG2 is binary image data

NFCData object

The NFCData object contains two properties:

Additional info

Listener Lifecycle

• Global Singleton: only one listener can be active at a time across your entire application.

• Replacement: setting a new listener in a new Configuration will replace any previously set listener.

• Auto-Cleanup: the listener is automatically cleared when the SDK session ends (when the user closes the SDK or verification completes).

Threading

Callbacks are executed on the main (UI) thread. If you need to perform heavy processing, it is recommended to dispatch work to a background thread:

override fun onNfcDataExtracted(nfcData: NfcData) {
        lifecycleScope.launch(Dispatchers.IO) {
            // Heavy processing on background thread
            processNfcData(nfcData)
        }
    }

@Override
    public void onNfcDataExtracted(@NotNull NfcData nfcData) {
        new Thread(() -> {
            // Heavy processing on background thread
            processNfcData(nfcData);
        }).start();
    }

Data Privacy

NFC data contains sensitive personal information:

• DG1: full name, date of birth, document number, nationality

• DG2: biometric face image

Ensure you:

• Handle this data in compliance with GDPR, CCPA, and other privacy regulations

• Implement appropriate security measures (encryption, secure storage)

• Only retain data for as long as necessary

• Have proper user consent mechanisms in place

Changelog