NFC相关

/**
 * 能够发现NFC的Activity
 */
public abstract class NfcActivity extends BaseActivity {

    /**
     * TECH_DISCOVERED、NDEF_DISCOVERED、TAG_DISCOVERED：NFC发现成功的标志
     */
    public boolean mIsNfcDiscoverd = false;

    private static final String TAG = NfcActivity.class.getSimpleName();

    @Override
    public void onNewIntent(Intent intent) {
        setIntent(intent);
    }

    @Override
    public void onResume() {
        super.onResume();

        String action = getIntent().getAction();

        mIsNfcDiscoverd = false;
        if (NfcAdapter.ACTION_NDEF_DISCOVERED.equals(action)) {
            Log.d(TAG, "ACTION_NDEF_DISCOVERED");
            mIsNfcDiscoverd = true;
        }
        else if (NfcAdapter.ACTION_TAG_DISCOVERED.equals(action)) {
            Log.d(TAG, "ACTION_TAG_DISCOVERED");
            mIsNfcDiscoverd = true;
        }
        else if (NfcAdapter.ACTION_TECH_DISCOVERED.equals(action)) {
            Log.d(TAG, "ACTION_TECH_DISCOVERED");
            mIsNfcDiscoverd = true;
        }
        else {
            //ACTION NULL DISCOVERED
        }

        if (mIsNfcDiscoverd) {

           // 发现NFC了，进来了。真格的来了。

            //1.  去初始化容器啥啥的
            。。。

            //2.  去取NDEFmessage
            getNdefMessages(getIntent());

           //3.  留给子类
            touchedNFC();

            //4.  禁用这一次的触摸，否则可能会又一次重新开始。
            getIntent().setAction(null);
        }
    }

    /**
     * NFC接触了。留给子类干点啥啥事情。。
     */
    protected void touchedNFC() {

    }

    /**
     * 去取NdefMessages
     */
    private NdefMessage[] getNdefMessages(Intent intent) {

        // 这里边 网络文章多为如下步骤。

        // 解析这个 intent
        NdefMessage[] msgs = null;
        String action = intent.getAction();

        Log.d(TAG, "_intent.getAction():" + action);

        Tag tagFromIntent = intent.getParcelableExtra(NfcAdapter.EXTRA_TAG);
        String[] list = tagFromIntent.getTechList();
        for (String v : list) { Log.d(TAG, "_getTechList():" + v); }

        Parcelable[] rawMsgs = intent.getParcelableArrayExtra(NfcAdapter.EXTRA_NDEF_MESSAGES);

        
        if (rawMsgs == null) {
            // 不识别的类型。。
            Log.d(TAG, "_Unknown tag type_");
            Log.d(TAG, "_rawMsgs == null " + action);

            byte[] empty = new byte[]{ };
            NdefRecord record = new NdefRecord(NdefRecord.TNF_UNKNOWN, empty, empty, empty);
            NdefMessage msg = new NdefMessage(new NdefRecord[]{record});
            msgs = new NdefMessage[]{msg};
        } else {
            Log.d(TAG, "_rawMsgs != null ");
            msgs = new NdefMessage[rawMsgs.length];
            String nDEFMessageNum = "NDEFMessage: " + rawMsgs.length + " Message(s)" + "\n";

            String recordContent = "";
            String recordNum = "";
            String recordId = "";
            String tnf = "";
            String type = "";
            String id = "";
            String payload = "";

            for (int i = 0; i < rawMsgs.length; i++) {

                msgs[i] = (NdefMessage) rawMsgs[i];

                for (int j = 0; j < msgs[i].getRecords().length; j++) {

                    recordNum = "NDEFMessage: "
                            + msgs[i].getRecords().length + " Record(s)"
                            + "\n\n";

                    recordId = "\"Record\", " + "\"" + String.valueOf(j)
                            + "\"" + "\n";
                    tnf = "\"TNF\", " + "\""
                            + getTnfName(msgs[i].getRecords()[j].getTnf())
                            + "\"" + "\n";
                    type = "\"Type\", " + "\""
                            + new String(msgs[i].getRecords()[j].getType())
                            + "\"" + "\n";
                    id = "\"ID\", " + "\""
                            + new String(msgs[i].getRecords()[j].getId())
                            + "\"" + "\n";

                    payload = "\"Payload\", "
                            + "\""
                            + new String(
                            msgs[i].getRecords()[j]
                                    .getPayload()) + "\""
                            + "\n";

                    String recordType = new String(msgs[i].getRecords()[j].getType()).toLowerCase();

                    try {
                            parsePayload(msgs[i].getRecords()[j], recordType)；
                    } catch (Exception e) {
                        // 又TM异常了。。。
                        e.printStackTrace();
                    }
                    recordContent += recordId + tnf + type + id + payload
                            + "\n";
                }
                Log.d(TAG, "得到了的_NDEF Message:" + nDEFMessageNum + recordNum + recordContent);
            }
        } 

        return msgs;
    }

    /**
     * 去解析NdefRecord
     */
    public void parsePayload(NdefRecord record, String recordType) {

        if (recordType.equals(***Type)) {
            try {
                NDEFinfo info = NDEFreader.getPrinterInfoFromNFC(record);
               。。。
            } catch (NDEFreadException e) {
                //异常了。。
                e.printStackTrace();
            }
        } else if (recordType.equals(lanType)) {
            try {
                NDEFinfo info = NDEFreader.getPrinterInfoFromNFC(record);
              。。。
            } catch (NDEFreadException e) {
                e.printStackTrace();
            }
        }
    }

/**
 * 支持NFC的界面类
 */
public class MyActivity extends NFCActivity {

    @Override
    public void onResume() {
        super.onResume();

        if(mIsNfcDiscoverd) {
            //NFC 被发现了，，要开始整啥啥任务。通常startService..
            //Service 起个异步task...
         }
   }
}

/**
 * 不支持NFC的界面类
 */
public class BaseActivity extends Activity {

protected NfcAdapter mNfcAdapter;
protected PendingIntent mPendingIntent;
protected IntentFilter[] mFilters;
protected String[][] mTechLists;

@Override
protected void onCreate(Bundle savedInstanceState) {
   super.onCreate(savedInstanceState);

  mNfcAdapter = NfcAdapter.getDefaultAdapter(this);
        mNfcAdapter = NfcAdapter.getDefaultAdapter(this);
        if (mNfcAdapter != null) {
            mPendingIntent = PendingIntent.getActivity(this, 0, new Intent(this,
                    getClass()).addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP), 0);

            // ・NDEF_DISCOVERED
            IntentFilter ndef = new IntentFilter(NfcAdapter.ACTION_NDEF_DISCOVERED);
            // ・TAG_DISCOVERED
            IntentFilter tag = new IntentFilter(NfcAdapter.ACTION_TAG_DISCOVERED);
            // ・TECH_DISCOVERED
            IntentFilter tech = new IntentFilter(NfcAdapter.ACTION_TECH_DISCOVERED);

            try {
                ndef.addDataType("application/octet-stream");
            } catch (IntentFilter.MalformedMimeTypeException e) {
                e.printStackTrace();
            }

            mFilters = new IntentFilter[]{tag, tech, ndef};
            mTechLists = new String[][]{new String[]{MifareClassic.class.getName()},
                    new String[]{MifareUltralight.class.getName()},
                    new String[]{IsoDep.class.getName()},
                    new String[]{NfcB.class.getName()},
                    new String[]{NfcF.class.getName()},
                    new String[]{NfcV.class.getName()},
                    new String[]{Ndef.class.getName()},
                    new String[]{NdefFormatable.class.getName()}
            };

        }
}

@Ovverride
public void onNewIntent(Intent intent) {
    String action = intent.getAction();
    boolean isNfcDiscovered = false;
    if (action.equals(NfcAdapter.ACTION_NDEF_DISCOVERED)){
        isNfcDiscovered = true;
    } else if(action.equals(NfcAdapter.ACTION_TAG_DISCOVERED)) {
        isNfcDiscovered = true;
    } else if(action.equals(NfcAdapter.ACTION_TECH_DISCOVERED)){
        isNfcDiscovered = true;
    } else {
        //Action null discovered.
    }

    if (isNfcDiscovered) {
      Toast toast = Toast.makeText(this,  "这个界面不支持NFC", Toast.LENGTH_LONG);
      toast.setGravity(Gravity.CENTER, 0, 0);
      toast.show();
    }
}

@Override
public void onResume() {
        super.onResume();

        if (mNfcAdapter != null) {
            mNfcAdapter.enableForegroundDispatch(this, mPendingIntent, mFilters, mTechLists);
        }
}

@Override
protected void onPause() {
        super.onPause();
        if (mNfcAdapter != null) {
            mNfcAdapter.disableForegroundDispatch(this);
        }
}

}