如何使用NFC发送简单的字符串

Question

我正在设计一个需要使用NFC传输简单字符串的应用程序，我已经尝试了多种设备，但仍然无法正常工作，即使这是直接从android开发者网站获取的代码段，也似乎出现了问题 1这是我尝试过的没有运气的代码：（

 @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_nfcdisplay);
        TextView textView = (TextView) findViewById(R.id.nfctesttext);
        mNfcAdapter = NfcAdapter.getDefaultAdapter(this);
        if (mNfcAdapter == null) {
            Toast.makeText(this, "NFC is not available", Toast.LENGTH_LONG).show();
            finish();
            return;
        }
        // Register callback
        mNfcAdapter.setNdefPushMessageCallback(this, this);
    }

    @Override
    public NdefMessage createNdefMessage(NfcEvent nfcEvent) {
        String text = ("Beam me up, Android!\n\n" +
                "Beam Time: " + System.currentTimeMillis());
        NdefMessage msg = new NdefMessage(
                new NdefRecord[] { createMime(
                        "application/vnd.com.example.android.beam", text.getBytes())
                        /**
                         * The Android Application Record (AAR) is commented out. When a device
                         * receives a push with an AAR in it, the application specified in the AAR
                         * is guaranteed to run. The AAR overrides the tag dispatch system.
                         * You can add it back in to guarantee that this
                         * activity starts when receiving a beamed message. For now, this code
                         * uses the tag dispatch system.
                        */
                        //,NdefRecord.createApplicationRecord("com.example.android.beam")
                });
        return msg;
    }
    @Override
    public void onResume() {
        super.onResume();
        // Check to see that the Activity started due to an Android Beam
        if (NfcAdapter.ACTION_NDEF_DISCOVERED.equals(getIntent().getAction())) {
            processIntent(getIntent());
        }
    }

    @Override
    public void onNewIntent(Intent intent) {
        // onResume gets called after this to handle the intent
        setIntent(intent);
    }

    /**
     * Parses the NDEF Message from the intent and prints to the TextView
     */
    void processIntent(Intent intent) {
        textView = (TextView) findViewById(R.id.textView);
        Parcelable[] rawMsgs = intent.getParcelableArrayExtra(
                NfcAdapter.EXTRA_NDEF_MESSAGES);
        // only one message sent during the beam
        NdefMessage msg = (NdefMessage) rawMsgs[0];
        // record 0 contains the MIME type, record 1 is the AAR, if present
        textView.setText(new String(msg.getRecords()[0].getPayload()));
    }

}