Как показать шестнадцатеричный уникальный идентификатор NF C Tag в моем приложении android NF C?

Question

Я уже делаю приложение для записи тегов, которое работает с поиском, я сохраняю текст данных для маркированной вещи (пример: компьютер 1) в теге NF C. И запись, и чтение работают нормально. Но мне нужно прочитать шестнадцатеричный идентификатор, который есть у каждого тега, когда я читаю информационный текст, который, как я знаю, имеет уникальный шестнадцатеричный идентификатор (потому что я вижу его, когда тестирую его с помощью приложения Google Play). Но я не знаю, как это сделать. Я действительно плохо умею кодировать, поэтому, пожалуйста, помогите мне.

Вот код:

public class MainActivity extends Activity {

    NfcAdapter mAdapter;
    Tag mTag;
    PendingIntent mPI;
    IntentFilter mFilter[]; 
    String userData,yo;

    boolean writeMode;
    Context context;
    TextView tvNFCContent, Timer,Low;

    Button start, pause, reset, lap ;
    long MillisecondTime, StartTime, TimeBuff, UpdateTime = 0L ;
    Handler handler;
    int Seconds, Minutes, MilliSeconds ;
    ListView listView ;
    String[] ListElements = new String[] {  };
    List<String> ListElementsArrayList ;
    ArrayAdapter<String> adapter ;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        tvNFCContent = (TextView) findViewById(R.id.data);
        Timer = (TextView)findViewById(R.id.timer);
        tvNFCContent.addTextChangedListener(watch);

        handler = new Handler() ;

        mAdapter = NfcAdapter.getDefaultAdapter(this);
        mPI = PendingIntent.getActivity(getApplicationContext(), 0,
                new Intent(this,getClass()).addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP),0 );

        IntentFilter tagDetected = new IntentFilter(NfcAdapter.ACTION_TAG_DISCOVERED);

        IntentFilter filter2 = new IntentFilter(NfcAdapter.ACTION_NDEF_DISCOVERED);
        mFilter = new IntentFilter[]{tagDetected,filter2};

        mAdapter = NfcAdapter.getDefaultAdapter(this);
        if (mAdapter == null) {
            // Stop here, we definitely need NFC
            Toast.makeText(this, "This device doesn't support NFC.", Toast.LENGTH_LONG).show();
            finish();
        }

        readFromIntent(getIntent());
    }


    private void readFromIntent(Intent intent) {
        String action = intent.getAction();
        if (NfcAdapter.ACTION_TAG_DISCOVERED.equals(action)
                || NfcAdapter.ACTION_TECH_DISCOVERED.equals(action)
                || NfcAdapter.ACTION_NDEF_DISCOVERED.equals(action)) 
        {
            Parcelable[] rawMsgs = intent.getParcelableArrayExtra(NfcAdapter.EXTRA_NDEF_MESSAGES);
            NdefMessage[] msgs = null;
            if (rawMsgs != null) {
                msgs = new NdefMessage[rawMsgs.length];
                for (int i = 0; i < rawMsgs.length; i++) {
                    msgs[i] = (NdefMessage) rawMsgs[i];
                }
            }                               
            buildTagViews(msgs);
        }
    }

    private void buildTagViews(NdefMessage[] msgs) {
        if (msgs == null || msgs.length == 0) return;

        String text = "";
//        String tagId = new String(msgs[0].getRecords()[0].getType());
        byte[] payload = msgs[0].getRecords()[0].getPayload();
        String textEncoding = ((payload[0] & 128) == 0) ? "UTF-8" : "UTF-16"; // Get the Text Encoding
        int languageCodeLength = payload[0] & 0063; // Get the Language Code, e.g. "en"
        // String languageCode = new String(payload, 1, languageCodeLength, "US-ASCII");

        try {

            text = new String(payload, languageCodeLength + 1, payload.length - languageCodeLength - 1, textEncoding);


        } catch (UnsupportedEncodingException e) {
            Log.e("UnsupportedEncoding", e.toString());
        }


     tvNFCContent.setText("NFC Content: " + text);
     TimeBuff += MillisecondTime;
     handler.removeCallbacks(runnable);

    }  

    NdefMessage[] getNdefMessage(Intent intent)
    {
        NdefMessage[] msgs = null;

        Parcelable[] rawMsgs = intent.getParcelableArrayExtra(NfcAdapter.EXTRA_NDEF_MESSAGES);
        if(rawMsgs != null)
        {
            msgs = new NdefMessage[rawMsgs.length];
            for(int i=0; i<rawMsgs.length; i++)
            {
                msgs[i] = (NdefMessage)rawMsgs[i];
            }
        }

        return msgs;
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    protected void onNewIntent(Intent intent) {
        // TODO Auto-generated method stub


        setIntent(intent);
        readFromIntent(intent);
        if (NfcAdapter.ACTION_TAG_DISCOVERED.equals(intent.getAction())){
            mTag = intent.getParcelableExtra(NfcAdapter.EXTRA_TAG);

        }

        super.onNewIntent(intent);

        if(intent.getAction().equals(NfcAdapter.ACTION_NDEF_DISCOVERED))
        {           
            Toast.makeText(getApplicationContext(),"Ndefdiscovered",Toast.LENGTH_SHORT).show();

        }else if(intent.getAction().equals(NfcAdapter.ACTION_TAG_DISCOVERED))
        {
            mTag = intent.getParcelableExtra(NfcAdapter.EXTRA_TAG);
            Toast.makeText(getApplicationContext(),"Smartcard detected",Toast.LENGTH_SHORT).show();

            StartTime = SystemClock.uptimeMillis();
            handler.postDelayed(runnable, 0);

            NdefMessage[] messages = getNdefMessage(intent);            
            if(messages == null)
            {
                Toast.makeText(getApplicationContext(),"There Is No Data",Toast.LENGTH_SHORT).show();
                return;
            }           
            byte[] payload = messages[0].getRecords()[0].getPayload();          
            userData = new String(payload);
        } else { 
            Toast.makeText(getApplicationContext(),"Undefined smartcard",Toast.LENGTH_SHORT).show();
        }

    }   

    public Runnable runnable = new Runnable() {

        public void run() {

            MillisecondTime = SystemClock.uptimeMillis() - StartTime;
            UpdateTime = TimeBuff + MillisecondTime;
            Seconds = (int) (UpdateTime / 1000);
            Minutes = Seconds / 60;
            Seconds = Seconds % 60;
            MilliSeconds = (int) (UpdateTime % 1000);
            Timer.setText("" + Minutes + ":"
                    + String.format("%02d", Seconds) + ":"
                    + String.format("%03d", MilliSeconds));

            handler.postDelayed(this, 0);
        }

    };


    @Override
    protected void onPause() {
        // TODO Auto-generated method stub
        super.onPause();
        mAdapter.disableForegroundDispatch(this);

    }

    @Override
    protected void onResume() {
        // TODO Auto-generated method stub
        super.onResume();
        mAdapter.enableForegroundDispatch(this, mPI, mFilter, null);

    }

    TextWatcher watch = new TextWatcher(){

        @Override
        public void afterTextChanged(Editable arg0) {
            // TODO Auto-generated method stub
        }

        @Override
        public void beforeTextChanged(CharSequence arg0, int arg1, int arg2,
                int arg3) {
            // TODO Auto-generated method stub
        }

        @Override
        public void onTextChanged(CharSequence s, int a, int b, int c) {
            // TODO Auto-generated method stub

        }
    };
}

Извините, я загружаю весь код, я просто хочу упростить fpr любой, кто хотел бы мне помочь.

Answer 1

Добавьте этот код в onNewIntent ()

Tag tag = intent.getParcelableExtra(NfcAdapter.EXTRA_TAG);
byte[] uid = tag.getId(); //This is the Unique IDentifier of the card

Используйте следующий метод, чтобы получить шестнадцатеричное значение

public static String getHexValue(final byte[] buffer) {
    if (buffer == null || buffer.length == 0) {
        return ("0x" + "[none]");
    }

    final StringBuffer sb = new StringBuffer();
    sb.append("0x");
    for (int i = 0; i < buffer.length - 1; i++) {
        sb.append(String.format("%02X%s", buffer[i], ""));
    }
    sb.append(String.format("%02X", buffer[buffer.length - 1]));

    return sb.toString();
}

Answer 2

Наконец-то я могу это сделать. Спасибо всем, кто мне помог. Вот полный код, которым я делюсь с вами.

package com.nfcreadfull;


import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.math.BigInteger;
import java.util.List;

import android.nfc.FormatException;
import android.nfc.NdefMessage;
import android.nfc.NdefRecord;
import android.nfc.NfcAdapter;
import android.nfc.Tag;
import android.nfc.tech.Ndef;
import android.nfc.tech.NdefFormatable;
import android.os.Bundle;
import android.os.Handler;
import android.os.Parcelable;
import android.os.SystemClock;
import android.app.Activity;
import android.app.PendingIntent;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.text.Editable;
import android.text.TextWatcher;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends Activity {


    NfcAdapter mAdapter;
    Tag mTag;
    PendingIntent mPI;
    IntentFilter mFilter[]; 
    String userData,yo;

    boolean writeMode;
    Context context;
    TextView tvNFCContent, Timer,Low, Uid;


    Button start, pause, reset, lap ;
    long MillisecondTime, StartTime, TimeBuff, UpdateTime = 0L ;
    int Seconds, Minutes, MilliSeconds ;
    ListView listView ;
    String[] ListElements = new String[] {  };
    List<String> ListElementsArrayList ;
    ArrayAdapter<String> adapter ;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);


        tvNFCContent = (TextView) findViewById(R.id.data);
        Timer = (TextView)findViewById(R.id.timer);
        Uid = (TextView)findViewById(R.id.uid); 

        mAdapter = NfcAdapter.getDefaultAdapter(this);
        mPI = PendingIntent.getActivity(getApplicationContext(), 0,
                new Intent(this,getClass()).addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP),0 );

        IntentFilter tagDetected = new IntentFilter(NfcAdapter.ACTION_TAG_DISCOVERED);

        IntentFilter filter2 = new IntentFilter(NfcAdapter.ACTION_NDEF_DISCOVERED);
        mFilter = new IntentFilter[]{tagDetected,filter2};


    mAdapter = NfcAdapter.getDefaultAdapter(this);
    if (mAdapter == null) {
        // Stop here, we definitely need NFC
        Toast.makeText(this, "This device doesn't support NFC.", Toast.LENGTH_LONG).show();
        finish();
    }

    readFromIntent(getIntent());

    }


    private void readFromIntent(Intent intent) {
        String action = intent.getAction();
        if (NfcAdapter.ACTION_TAG_DISCOVERED.equals(action)
                || NfcAdapter.ACTION_TECH_DISCOVERED.equals(action)
                || NfcAdapter.ACTION_NDEF_DISCOVERED.equals(action)) 


        {
            Parcelable[] rawMsgs = intent.getParcelableArrayExtra(NfcAdapter.EXTRA_NDEF_MESSAGES);
            NdefMessage[] msgs = null;
            if (rawMsgs != null) {
                msgs = new NdefMessage[rawMsgs.length];
                for (int i = 0; i < rawMsgs.length; i++) {
                    msgs[i] = (NdefMessage) rawMsgs[i];


                }
            }                               
            buildTagViews(msgs);
        }



}

    private void buildTagViews(NdefMessage[] msgs) {
        if (msgs == null || msgs.length == 0) return;

        String text = "";
//        String tagId = new String(msgs[0].getRecords()[0].getType());
        byte[] payload = msgs[0].getRecords()[0].getPayload();
        String textEncoding = ((payload[0] & 128) == 0) ? "UTF-8" : "UTF-16"; // Get the Text Encoding
        int languageCodeLength = payload[0] & 0063; // Get the Language Code, e.g. "en"
        // String languageCode = new String(payload, 1, languageCodeLength, "US-ASCII");

        try {

            text = new String(payload, languageCodeLength + 1, payload.length - languageCodeLength - 1, textEncoding);


        } catch (UnsupportedEncodingException e) {
            Log.e("UnsupportedEncoding", e.toString());
        }


     tvNFCContent.setText("NFC Content: " + text);

    }  



    NdefMessage[] getNdefMessage(Intent intent)
    {
        NdefMessage[] msgs = null;

        Parcelable[] rawMsgs = intent.getParcelableArrayExtra(NfcAdapter.EXTRA_NDEF_MESSAGES);
        if(rawMsgs != null)
        {
            msgs = new NdefMessage[rawMsgs.length];
            for(int i=0; i<rawMsgs.length; i++)
            {
                msgs[i] = (NdefMessage)rawMsgs[i];
            }
        }

        return msgs;
    }





    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    protected void onNewIntent(Intent intent) {
        // TODO Auto-generated method stub

        Uid.setText(ByteArrayToHexString(intent.getByteArrayExtra(NfcAdapter.EXTRA_ID)));




        setIntent(intent);
        readFromIntent(intent);
        if (NfcAdapter.ACTION_TAG_DISCOVERED.equals(intent.getAction())){
            mTag = intent.getParcelableExtra(NfcAdapter.EXTRA_TAG);

        }

        super.onNewIntent(intent);

        if(intent.getAction().equals(NfcAdapter.ACTION_NDEF_DISCOVERED))
        {           
            Toast.makeText(getApplicationContext(),"Smartcard detected",Toast.LENGTH_SHORT).show();

        }else if(intent.getAction().equals(NfcAdapter.ACTION_TAG_DISCOVERED))
        {
            mTag = intent.getParcelableExtra(NfcAdapter.EXTRA_TAG);

            NdefMessage[] messages = getNdefMessage(intent);            
            if(messages == null)
            {
                Toast.makeText(getApplicationContext(),"There Is No Data",Toast.LENGTH_SHORT).show();
                return;
            }           
            byte[] payload = messages[0].getRecords()[0].getPayload();          
            userData = new String(payload);



        }else
        {
            Toast.makeText(getApplicationContext(),"Undefined smartcard",Toast.LENGTH_SHORT).show();
        }




        if (NfcAdapter.ACTION_NDEF_DISCOVERED.equals(intent.getAction())) {
            // While with ForegroundDispatch the NDEF message has already been read
            // And passed to us in the intent and thus the time the App spends "read" the NFC card is Zero
            // We want to time time the read, so now we have been notified that a NDEF card is in range
            // Try and read from it

            // Get the Tag from the intent
            Tag tag = intent.getParcelableExtra(NfcAdapter.EXTRA_TAG);

            long startTime = 0;
            long endTime = 0;

            try {
                // Create an NDEF tag object
                Ndef ndefTag = Ndef.get(tag);

                // This is the I/O operation to read the card and format the result to an NDEF message
                // Nothing is done with the result to not add any time to it, as we are timing this
                startTime = System.currentTimeMillis();
                ndefTag.connect();
                ndefTag.getNdefMessage();
                endTime = System.currentTimeMillis();
                ndefTag.close();
            } catch (Exception e) {
                Log.e("NFC", e.toString());
            }

            MillisecondTime = endTime - startTime;

            UpdateTime = MillisecondTime;

            Seconds = (int) (UpdateTime / 1000);

            Minutes = Seconds / 60;

            Seconds = Seconds % 60;

            MilliSeconds = (int) (UpdateTime % 1000);

            Timer.setText("" + Minutes + ":"
                    + String.format("%02d", Seconds) + "."
                    + String.format("%03d", MilliSeconds));



            //Log.v("NFC", "Time to read in milliseconds is: " + (endTime - startTime));
          //Timer.setText("00:00:0.0"+(endTime - startTime));

        }

    }


    @Override
    protected void onPause() {
        // TODO Auto-generated method stub
        super.onPause();
        mAdapter.disableForegroundDispatch(this);

    }

    @Override
    protected void onResume() {
        // TODO Auto-generated method stub
        super.onResume();   
        IntentFilter tagDetected = new IntentFilter(NfcAdapter.ACTION_TAG_DISCOVERED);
        IntentFilter ndefDetected = new IntentFilter(NfcAdapter.ACTION_NDEF_DISCOVERED);
        try {
            ndefDetected.addDataType("*/*");
        } catch (IntentFilter.MalformedMimeTypeException e) {}
        IntentFilter techDetected = new IntentFilter(NfcAdapter.ACTION_TECH_DISCOVERED);
        IntentFilter[] nfcIntentFilter = new IntentFilter[]{ndefDetected,techDetected,tagDetected};

        PendingIntent pendingIntent = PendingIntent.getActivity(
                this, 0, new Intent(this, getClass()).addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP), 0);
        if(mAdapter!= null)
            mAdapter.enableForegroundDispatch(this, pendingIntent, nfcIntentFilter, null);


    }


     private String getHex(byte[] bytes) {
         if (bytes == null) {
                return null;
            }
            char[] hexChars = new char[bytes.length * 2];
            final char[] hexArray = "0123456789abcdef".toCharArray();
            for (int j = 0; j < bytes.length; j++) {
                int v = bytes[j] & 0xFF;
                hexChars[j * 2] = hexArray[v >>> 4];
                hexChars[j * 2 + 1] = hexArray[v & 0x0F];
            }
            return new String(hexChars);
        }

    private long getDec(byte[] bytes) {
        long result = 0;
        long factor = 1;
        for (int i = 0; i < bytes.length; ++i) {
            long value = bytes[i] & 0xffl;
            result += value * factor;
            factor *= 256l;
        }
        return result;
    }



    private String ByteArrayToHexString(byte [] inarray) {

        Log.d("ByteArrayToHexString", inarray.toString());

        int i, j, in;
        String [] hex = {"0","1","2","3","4","5","6","7","8","9","A","B","C","D","E","F"};
        String out= "";

        for(j = 0 ; j < inarray.length ; ++j)
        {
            in = (int) inarray[j] & 0xff;
            i = (in >> 4) & 0x0f;
            out += hex[i];
            i = in & 0x0f;
            out += hex[i];
        }

        Log.d("ByteArrayToHexString", String.format("%0" + (inarray.length * 2) + "X", new BigInteger(1,inarray)));


        return out;
    }


}