Reading multiple NFC tags in Android. IsoDep tag will not read while the screen is unlocked

I am trying to create an application that can read two different types of NFC tags. It is assumed that HCE-IsoDep is emulated on Nexus 5, and one is the Ndef tag. However, I ran into a small problem:

I manage to read both types of tags, but not the way I want to do it. The Ndef tag is not a problem at all. When I try to read the HCE tag, I run into my problem. I can only read the tag when the phone is on, which I imitate the tag is locked (the screen is on, but the lock is on). Whenever I unlock the screen, it will no longer interact, and as far as I can understand, it is trying to turn on the beam.

If I try to do this without onNewIntentand just go to onTagDiscovered, it works at the same time when the HCE device is locked and unlocked, but then I can’t read the Ndef tag. In logcat, I get the message: NfcService LLCP Activation Messagewhen I read the HCE tag when unlocking.

When locked, I get the message NativeNfcTag Connect to a tag with a different handle(and before that I get: audio_hw_primary select_devices: out_snd_device(2: speaker) in_snd_device(0: ))

My code is as follows:

Main:

public class NfcReader extends Activity implements OnMessageReceived {

private static String TAG = NfcReader.class.getSimpleName();

private Button sendButton;
private ProgressBar callProgress;


private NfcAdapter nfcAdapter;
private PendingIntent pIntent;
private IntentFilter[] writeTagFilters;
private String[][] mTechLists;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    TextView dateView = (TextView) findViewById(R.id.dateTextView);

    nfcAdapter = NfcAdapter.getDefaultAdapter(this);
    pIntent = PendingIntent.getActivity(this, 0, new Intent(this, getClass()).addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP), 0);

    IntentFilter tagDetected = new IntentFilter(NfcAdapter.ACTION_TAG_DISCOVERED);
    writeTagFilters = new IntentFilter[] { tagDetected };

    mTechLists = new String[][] {new String[] {
            Ndef.class.getName(),
            IsoDep.class.getName()
    }};
}

@Override
protected void onPause() {
    super.onPause();
    disableForegroundMode();
}

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

public void enableForegroundMode() {
    Log.d(TAG, "onResume");
    nfcAdapter.enableForegroundDispatch(this, pIntent, writeTagFilters, mTechLists);
}

public void disableForegroundMode() {
    Log.d(TAG, "onPause");
    nfcAdapter.disableForegroundDispatch(this);
}

@Override
public void onNewIntent(Intent intent) {
    Log.d(TAG, "onNewIntent");

    if(NfcAdapter.ACTION_TAG_DISCOVERED.equals(intent.getAction())){

        Tag tag = intent.getParcelableExtra(NfcAdapter.EXTRA_TAG);
        Ndef nDef = Ndef.get(tag);

        if (nDef != null) {
            onNdefDiscovered(tag);
        }
        else {
            onTagDiscovered(tag);
        }
    }
}

public void onNdefDiscovered(Tag tag) {
    Log.d(TAG, "Ndef found");
    new ReadTag().execute(tag);
}

public void onTagDiscovered(Tag tag) {
    Log.d(TAG, "HCEfound"); 
    IsoDep isoDep = IsoDep.get(tag);
    IsoDepTransceiver transceiver = new IsoDepTransceiver(isoDep, this);
    transceiver.run();

}

@Override
public void onMessage(final byte[] message) {
    runOnUiThread(new Runnable() {

        @Override
        public void run() {
            String readFromHce = new String(message);
            TextView result = (TextView) findViewById(R.id.refTextView);
            result.setText(readFromHce);

        }
    });
}

@Override
public void onError(Exception exception) {
    onMessage(exception.getMessage().getBytes());
}
}

manifest:

<uses-sdk
    android:minSdkVersion="19"
    android:targetSdkVersion="19" />

<uses-permission 
    android:name="android.permission.INTERNET" />

<uses-permission 
    android:name="android.permission.NFC" />

<uses-feature
    android:name="android.hardware.nfc"
    android:required="true" />

<application
    android:allowBackup="true"
    android:icon="@drawable/ic_launcher"
    android:label="@string/app_name" >
    <activity
        android:name=".HceReader"
        android:label="@string/app_name" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
        <intent-filter>
            <action android:name="android.nfc.action.NDEF_DISCOVERED"/>
            <action android:name="android.nfc.action.TECH_DISCOVERED"/>
            <action android:name="android.nfc.action.TAG_DISCOVERED" />
            <category android:name="android.intent.category.DEFAULT" />
            <data android:mimeType="text/plain" />
        </intent-filter>

        <meta-data
            android:name="android.nfc.action.TECH_DISCOVERED"
            android:resource="@xml/filter_nfc"/>

filter_nfc.xml

<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">

    <tech-list>
        <tech>android.nfc.tech.IsoDep</tech>
    </tech-list>

    <tech-list>
        <tech>android.nfc.tech.Ndef</tech>
    </tech-list>
</resources>

Does anyone have an idea what I'm doing wrong? I searched around quite a bit, not finding a solution for this. So again. I can read the Ndef tag without any problems. I can only read the emultated IsoDep tag when the screen on the HCE device is locked.

Thanks for any help
Relationship

Edit: code below works

public class NfcReader extends Activity implements OnMessageReceived, ReaderCallback {

private static String TAG = NfcReader.class.getSimpleName();

private NfcAdapter nfcAdapter;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    TextView result = (TextView) findViewById(R.id.refTextView);

    nfcAdapter = NfcAdapter.getDefaultAdapter(this);
}

@Override
protected void onPause() {
    super.onPause();
    nfcAdapter.disableReaderMode(this);
}

@Override
protected void onResume() {
    super.onResume();
    nfcAdapter.enableReaderMode(this, this, NfcAdapter.FLAG_READER_NFC_A, null);
}

public void onTagDiscovered(Tag tag) {
    Log.d(TAG, "Tag Found"); 

    Ndef nDef = Ndef.get(tag);
    IsoDep isoDep = IsoDep.get(tag);

    if (nDef != null) {
        new ReadTag().execute(tag);
    }
    else if (isoDep != null){
        IsoDepTransceiver transceiver = new IsoDepTransceiver(isoDep, this);
        transceiver.run();      
    }
}

@Override
public void onMessage(final byte[] message) {
    runOnUiThread(new Runnable() {

        @Override
        public void run() {
            String readFromHce = new String(message);
            TextView result = (TextView) findViewById(R.id.refTextView);
            result.setText(readFromHce);
        }
    });
}

@Override
public void onError(Exception exception) {
    onMessage(exception.getMessage().getBytes());
}
}

Many thanks to the NFC guy for the tip.

+4
2

Android 4.4 enableReaderMode() .

NFC / NFC, (Android Beam) NFC .

, Android Android, FLAG_READER_NFC_A FLAG_READER_SKIP_NDEF_CHECK.

+6

. , , , .

( android beam), ( ) , .

, : SIM- NFC , SIM-. peer-to-peer , , IsoDep.

, , . .

, , (, ).

Android . Android Beam , Beam . peer-to-peer - . , Google , .

+1

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