NFC detection fails sometimes

[rajeshkanna777]

Prerequisites

• Put an X between the brackets on this line if you have done all of the following:
  • My Android device/devices supports BLE and has Android OS version >= 4.4
  • My Android device/devices have Bluetooth enabled
  • My app has Location Permissions granted

Basic information

I have few NFC beacons. When i tap the beacon on to the backside of the phone, some times beacon gets detected and sometimes not. I tried the same in Estimote app also. Even in Estimote app, the Quick connect menu is not working sometimes.

**Expected behavior:**When i tap the NFC beacon i have to read the the Beacon identifier and mac address everytime,

Actual behavior: When i tap the beacon some times i am not able to read it via NFC (i.e Not detected).

Here my code

   private NfcAdapter mNfcAdapter;
    protected void onCreate(Bundle savedInstanceState) {
 mNfcAdapter = NfcAdapter.getDefaultAdapter(this);
}

    @Override
    public void onResume() {
        super.onResume();
        try {
            SystemRequirementsChecker.checkWithDefaultDialogs(this);
            IntentFilter tagDetected = new IntentFilter(NfcAdapter.ACTION_TAG_DISCOVERED);
            IntentFilter ndefDetected = new IntentFilter(NfcAdapter.ACTION_NDEF_DISCOVERED);
            IntentFilter[] nfcIntentFilter = new IntentFilter[]{tagDetected, ndefDetected};
            PendingIntent pendingIntent = PendingIntent.getActivity(
                    this, 0, new Intent(this, getClass()).addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP), 0);
            if (mNfcAdapter != null)
                mNfcAdapter.enableForegroundDispatch(this, pendingIntent, nfcIntentFilter, null);
        } catch (Exception e) {
            Log.e(TAG, "Nfc adapter failed");
        }
    }


 @Override
    protected void onNewIntent(Intent intent) {
        try {
            if (intent.getAction() != null && 
                   intent.getAction().equals(NfcAdapter.ACTION_TAG_DISCOVERED)) {
                Parcelable[] rawMsgs = intent.getParcelableArrayExtra(
                        NfcAdapter.EXTRA_NDEF_MESSAGES);
                if (rawMsgs != null) {
                    for (Parcelable rawMsg : rawMsgs) {
                        NdefMessage msg = (NdefMessage) rawMsg;
                        NdefRecord[] records = msg.getRecords();
                        for (NdefRecord record : records) {
                            if (record.getTnf() == NdefRecord.TNF_EXTERNAL_TYPE) {
                                String type = new String(record.getType(), Charset.forName("ascii"));
                                if ("estimote.com:id".equals(type)) {
                                    deviceId = DeviceId.fromBytes(record.getPayload());
                                } else if ("estimote.com:mac".equals(type)) {
                                    byte[] revMac = new byte[record.getPayload().length];
                                    for (int j = 0; j < revMac.length; j++) {
                                        revMac[j] = record.getPayload()[revMac.length - j - 1];
                                    }
                                    macAddress = MacAddress.fromBytes(revMac);
                                }
                            }
                        }
                    }
        } catch (Exception e) {
            Log.e(TAG, "New intend failed");
        }
    }


 @Override
    public void onDestroy() {
        super.onDestroy();
     mNfcAdapter=null;
    }

When beacons are not detected, i get rawMsgs as null in the following lines of code
Parcelable[] rawMsgs = intent.getParcelableArrayExtra(
NfcAdapter.EXTRA_NDEF_MESSAGES);

[heypiotr]

The NFC antenna in Estimote Beacons isn't particularly strong, so it sometimes requires a few tries to align the antenna in the beacon with the antenna in the smartphone properly. Not much to do here on the software/SDK side, so I've closed this issue.

You can start a discussion on our forums, tell us how you want to use NFC (configuration/deployment? or in your app?), and we can try to help, maybe suggest some alternative solution, etc.