Reading an NDEF message from an NFC tag from an Android application

Question

I am trying to create an application using NFC and I just want to try and read an NFC tag and get the text message from the tag and place it into a TextView. I have code for it already, but nothing happens when I try to pair the phone with an NFC tag. Here is my code and could someone please look at it and see what I am doing wrong and what needs to be done to fix the issue please: ``` Button measurementsDataButton; NfcAdapter myNfcAdapter; PendingIntent myPendingIntent; IntentFilter ndef; IntentFilter[] filters; String[][] techLists; int mCount; TextView mText; String payload; byte payloadHeader; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_nfc_scanner); final ActionBar actionBar = getActionBar(); actionBar.setDisplayHomeAsUpEnabled(true); mText = (TextView) findViewById(R.id.flowTextView1); measurementsDataButton = (Button) findViewById(R.id.measurementsButton1); measurementsDataButton.setOnClickL…

Accepted Answer

example of code for send-receive NDEF TAG:

```
public class MainActivity extends AppCompatActivity implements NfcAdapter.CreateNdefMessageCallback {

private NfcAdapter mNfcAdapter;
TextView tv;
private PendingIntent mPendingIntent;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

tv = (TextView) findViewById(R.id.textViewReceivedMessage);

NfcManager nfcManager = (NfcManager) getSystemService(NFC_SERVICE);
    mNfcAdapter = nfcManager.getDefaultAdapter();

mPendingIntent = PendingIntent.getActivity(this, 0, new Intent(this, getClass())
            .addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP), 0);
}

private static NdefMessage getTestMessage() {
    byte[] mimeBytes = "application/com.android.cts.verifier.nfc"
            .getBytes(Charset.forName("US-ASCII"));
    byte[] id = new byte[] {1, 3, 3, 7};
    byte[] payload = "CTS Verifier NDEF Push Tag".getBytes(Charset.forName("US-ASCII"));
    return new NdefMessage(new NdefRecord[] {
            new NdefRecord(NdefRecord.TNF_MIME_MEDIA, mimeBytes, id, payload)
    });
}

@Override
protected void onResume() {
    super.onResume();

mNfcAdapter.enableForegroundDispatch(this, mPendingIntent, null, null);
    mNfcAdapter.setNdefPushMessageCallback(this, this);
}

// sending message
@Override
public NdefMessage createNdefMessage(NfcEvent event) {
    return getTestMessage();
}

private NdefMessage[] getNdefMessages(Intent intent) {
    Parcelable[] rawMessages = intent.getParcelableArrayExtra(NfcAdapter.EXTRA_NDEF_MESSAGES);
    if (rawMessages != null) {
        NdefMessage[] messages = new NdefMessage[rawMessages.length];
        for (int i = 0; i < messages.length; i++) {
            messages[i] = (NdefMessage) rawMessages[i];
        }
        return messages;
    } else {
        return null;
    }
}

static String displayByteArray(byte[] bytes) {
    String res="";
    StringBuilder builder = new StringBuilder().append("[");
    for (int i = 0; i < bytes.length; i++) {
        res+=(char)bytes[i];
    }
    return res;
}

// displaying message
@Override
protected void onNewIntent(Intent intent) {
    super.onNewIntent(intent);

NdefMessage[] messages = getNdefMessages(intent);
    tv.setText(displayByteArray(messages[0].toByteArray()));
}
```

}

Reading an NDEF message from an NFC tag from an Android application

Solution

Problem