NFC技术：读写非NDEF格式的数据

//向nfc标签读写MifareUltraligh格式的数据
public class MainActivity extends Activity {
    private CheckBox mwriteData;
    private NfcAdapter mNfcAdapter;
    private PendingIntent mPendingIntent;

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

        mwriteData = (CheckBox) findViewById(R.id.checkBox1);
        mNfcAdapter = NfcAdapter.getDefaultAdapter(this);
        mPendingIntent = PendingIntent.getActivity(this, 0, new Intent(this,
                getClass()), 0);
    }

    @Override
    protected void onNewIntent(Intent intent) {
        // TODO Auto-generated method stub
        super.onNewIntent(intent);
        Tag tag = intent.getParcelableExtra(NfcAdapter.EXTRA_TAG);

        String[] techList = tag.getTechList();
        boolean haveMifareUltralight = false;
        for (String tech : techList) {
            if (tech.indexOf("MifareUltralight") >= 0) {
                haveMifareUltralight = true;
                break;
            }

        }
        if (!haveMifareUltralight) {
            Toast.makeText(this, "不支持MifareUltralight格式数据", 0).show();
            return;
        }
        // 选中为写数据
        if (mwriteData.isChecked()) {
            writeTag(tag);

        }
        // 否则为读数据
        else {
            String data = readTag(tag);
            if (data != null) {
                Toast.makeText(this, data, 0).show();
            }
        }

    }

    @Override
    protected void onResume() {
        // TODO Auto-generated method stub
        super.onResume();
        if (mNfcAdapter != null) {
            mNfcAdapter.enableForegroundDispatch(this, mPendingIntent, null,
                    null);
        }
    }

    @Override
    protected void onPause() {
        // TODO Auto-generated method stub
        super.onPause();
        if (mNfcAdapter != null) {
            mNfcAdapter.disableForegroundDispatch(this);
        }
    }

    // 向nfc标签写MifareUltralight格式数据
    public void writeTag(Tag tag) {
        MifareUltralight ultralight = MifareUltralight.get(tag);
        try {
            ultralight.connect();
            ultralight.writePage(4, "中国".getBytes(Charset.forName("GB2312")));
            ultralight.writePage(5, "美国".getBytes(Charset.forName("GB2312")));
            ultralight.writePage(6, "韩国".getBytes(Charset.forName("GB2312")));
            ultralight.writePage(7, "日本".getBytes(Charset.forName("GB2312")));

            Toast.makeText(this, "写入MifareUltralight格式数据成功", 0).show();
        } catch (Exception e) {
            // TODO: handle exception
        } finally {
            try {
                ultralight.close();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }

    public String readTag(Tag tag) {
        MifareUltralight ultralight = MifareUltralight.get(tag);
        try {
            ultralight.connect();
            byte[] data = ultralight.readPages(4);
            return new String(data, Charset.forName("GB2312"));

        } catch (Exception e) {
            // TODO: handle exception
        } finally {

            try {
                ultralight.close();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }

        }
        return null;

    }
}