用NFC建立蓝牙连接聊天软件

原理流程 NFC发送A的蓝牙地址给B，B接受到A的蓝牙地址并与之配对建立socket连接，通过socket传送文件

package com.example.huanghanqing.testnfcbluetoothchat;

import android.app.ActionBar;

import android.app.Activity;

import android.bluetooth.BluetoothAdapter;

import android.bluetooth.BluetoothDevice;

import android.content.Intent;

import android.nfc.NdefMessage;

import android.nfc.NdefRecord;

import android.nfc.NfcAdapter;

import android.nfc.NfcEvent;

import android.os.Bundle;

import android.os.Handler;

import android.os.Message;

import android.os.Parcelable;

import android.util.Log;

import android.view.KeyEvent;

import android.view.Menu;

import android.view.MenuInflater;

import android.view.MenuItem;

import android.view.View;

import android.view.Window;

import android.view.View.OnClickListener;

import android.view.inputmethod.EditorInfo;

import android.widget.ArrayAdapter;

import android.widget.Button;

import android.widget.EditText;

import android.widget.ListView;

import android.widget.TextView;

import android.widget.Toast;

import static android.nfc.NdefRecord.createMime;

/**

 * This is the main Activity that displays the current chat session.

 */

public class BluetoothChat extends Activity implements NfcAdapter.CreateNdefMessageCallback{

    // Debugging

    private static final String TAG = "BluetoothChat";

    private static final boolean D = true;

    // Message types sent from the BluetoothChatService Handler

    public static final int MESSAGE_STATE_CHANGE = 1;

    public static final int MESSAGE_READ = 2;

    public static final int MESSAGE_WRITE = 3;

    public static final int MESSAGE_DEVICE_NAME = 4;

    public static final int MESSAGE_TOAST = 5;

    // Key names received from the BluetoothChatService Handler

    public static final String DEVICE_NAME = "device_name";

    public static final String TOAST = "toast";

    // Intent request codes

    private static final int REQUEST_CONNECT_DEVICE_SECURE = 1;

    private static final int REQUEST_CONNECT_DEVICE_INSECURE = 2;

    private static final int REQUEST_ENABLE_BT = 3;

    // Layout Views

    private ListView mConversationView;

    private EditText mOutEditText;

    private Button mSendButton;

    // Name of the connected device

    private String mConnectedDeviceName = null;

    // Array adapter for the conversation thread

    private ArrayAdapter<String> mConversationArrayAdapter;

    // String buffer for outgoing messages

    private StringBuffer mOutStringBuffer;

    // Local Bluetooth adapter

    private BluetoothAdapter mBluetoothAdapter = null;

    // Member object for the chat services

    private BluetoothChatService mChatService = null;

    private  NfcAdapter mNfcAdapter;

    @Override

    public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        System.out.println("onCreate*********************");

        if(D) Log.e(TAG, "+++ ON CREATE ++");

        if(D) Log.e(TAG, "+++ ON CREATE ********************88");

        getWindow().requestFeature(Window.FEATURE_ACTION_BAR);

        // Set up the window layout

        setContentView(R.layout.main);

        // Get local Bluetooth adapter

        mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();

        // If the adapter is null, then Bluetooth is not supported

        if (mBluetoothAdapter == null) {

            Toast.makeText(this, "Bluetooth is not available", Toast.LENGTH_LONG).show();

            finish();

            return;

        }

        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 void onStart() {

        super.onStart();

        if(D) Log.e(TAG, "++ ON START ++");

        // If BT is not on, request that it be enabled.

        // setupChat() will then be called during onActivityResult

        if (!mBluetoothAdapter.isEnabled()) {

            //提示用户打开；

            Intent enableIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);

            startActivityForResult(enableIntent, REQUEST_ENABLE_BT);

            //直接打开；

            //    mBluetoothAdapter.enable();

            //     setupChat();

            // Otherwise, setup the chat session

        } else {

            if (mChatService == null) setupChat();

        }

    }

    @Override

    public synchronized void onResume() {

        super.onResume();

        if(D) Log.e(TAG, "onResume********************");

        if(D) Log.e(TAG, "+ ON RESUME +");

        if (NfcAdapter.ACTION_NDEF_DISCOVERED.equals(getIntent().getAction())) {

            if(D) Log.e(TAG, "ACTION_NDEF_DISCOVERED");

            processIntent(getIntent());

        }

        // Performing this check in onResume() covers the case in which BT was

        // not enabled during onStart(), so we were paused to enable it...

        // onResume() will be called when ACTION_REQUEST_ENABLE activity returns.

        if (mChatService != null) {

            // Only if the state is STATE_NONE, do we know that we haven't started already

            if (mChatService.getState() == BluetoothChatService.STATE_NONE) {

                // Start the Bluetooth chat services

                mChatService.start();

            }

        }

    }

    private void setupChat() {

        Log.d(TAG, "setupChat()");

        // Initialize the array adapter for the conversation thread

        mConversationArrayAdapter = new ArrayAdapter<String>(this, R.layout.message);

        mConversationView = (ListView) findViewById(R.id.in);

        mConversationView.setAdapter(mConversationArrayAdapter);

        // Initialize the compose field with a listener for the return key

        mOutEditText = (EditText) findViewById(R.id.edit_text_out);

        mOutEditText.setOnEditorActionListener(mWriteListener);

        // Initialize the send button with a listener that for click events

        mSendButton = (Button) findViewById(R.id.button_send);

        mSendButton.setOnClickListener(new OnClickListener() {

            public void onClick(View v) {

                // Send a message using content of the edit text widget

                TextView view = (TextView) findViewById(R.id.edit_text_out);

                String message = view.getText().toString();

                sendMessage(message);

            }

        });

        // Initialize the BluetoothChatService to perform bluetooth connections

        mChatService = new BluetoothChatService(this, mHandler);

        // Initialize the buffer for o
4000
utgoing messages

        mOutStringBuffer = new StringBuffer("");

    }

    @Override

    protected void onNewIntent(Intent intent) {

        if(D) Log.e(TAG, "onNewIntent**************");

        setIntent(intent);

    }

    @Override

    public synchronized void onPause() {

        super.onPause();

        if(D) Log.e(TAG, "- ON PAUSE -");

    }

    @Override

    public void onStop() {

        super.onStop();

        if(D) Log.e(TAG, "-- ON STOP --");

    }

    @Override

    public void onDestroy() {

        super.onDestroy();

        // Stop the Bluetooth chat services

        if (mChatService != null) mChatService.stop();

        if(D) Log.e(TAG, "--- ON DESTROY ---");

    }

    private void ensureDiscoverable() {

        if(D) Log.d(TAG, "ensure discoverable");

        if (mBluetoothAdapter.getScanMode() !=

                BluetoothAdapter.SCAN_MODE_CONNECTABLE_DISCOVERABLE) {

            Intent discoverableIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_DISCOVERABLE);

            discoverableIntent.putExtra(BluetoothAdapter.EXTRA_DISCOVERABLE_DURATION, 300);

            startActivity(discoverableIntent);

        }

    }

    /**

     * Sends a message.

     * @param message  A string of text to send.

     */

    private void sendMessage(String message) {

        // Check that we're actually connected before trying anything

        if (mChatService.getState() != BluetoothChatService.STATE_CONNECTED) {

            Toast.makeText(this, R.string.not_connected, Toast.LENGTH_SHORT).show();

            return;

        }

        // Check that there's actually something to send

        if (message.length() > 0) {

            // Get the message bytes and tell the BluetoothChatService to write

            byte[] send = message.getBytes();

            mChatService.write(send);

            // Reset out string buffer to zero and clear the edit text field

            mOutStringBuffer.setLength(0);

            mOutEditText.setText(mOutStringBuffer);

        }

    }

    // The action listener for the EditText widget, to listen for the return key

    private TextView.OnEditorActionListener mWriteListener =

            new TextView.OnEditorActionListener() {

                public boolean onEditorAction(TextView view, int actionId, KeyEvent event) {

                    // If the action is a key-up event on the return key, send the message

                    if (actionId == EditorInfo.IME_NULL && event.getAction() == KeyEvent.ACTION_UP) {

                        String message = view.getText().toString();

                        sendMessage(message);

                    }

                    if(D) Log.i(TAG, "END onEditorAction");

                    return true;

                }

            };

    private final void setStatus(int resId) {

        final ActionBar actionBar = getActionBar();

        actionBar.setSubtitle(resId);

    }

    private final void setStatus(CharSequence subTitle) {

        final ActionBar actionBar = getActionBar();

        actionBar.setSubtitle(subTitle);

    }

    // The Handler that gets information back from the BluetoothChatService

    private final Handler mHandler = new Handler() {

        @Override

        public void handleMessage(Message msg) {

            switch (msg.what) {

                case MESSAGE_STATE_CHANGE:

                    if(D) Log.i(TAG, "MESSAGE_STATE_CHANGE: " + msg.arg1);

                    switch (msg.arg1) {

                        case BluetoothChatService.STATE_CONNECTED:

                            setStatus(getString(R.string.title_connected_to, mConnectedDeviceName));

                            mConversationArrayAdapter.clear();

                            break;

                        case BluetoothChatService.STATE_CONNECTING:

                            setStatus(R.string.title_connecting);

                            break;

                        case BluetoothChatService.STATE_LISTEN:

                        case BluetoothChatService.STATE_NONE:

                            setStatus(R.string.title_not_connected);

                            break;

                    }

                    break;

                case MESSAGE_WRITE:

                    byte[] writeBuf = (byte[]) msg.obj;

                    // construct a string from the buffer

                    String writeMessage = new String(writeBuf);

                    mConversationArrayAdapter.add("Me:  " + writeMessage);

                    break;

                case MESSAGE_READ:

                    byte[] readBuf = (byte[]) msg.obj;

                    // construct a string from the valid bytes in the buffer

                    String readMessage = new String(readBuf, 0, msg.arg1);

                    mConversationArrayAdapter.add(mConnectedDeviceName+":  " + readMessage);

                    break;

                case MESSAGE_DEVICE_NAME:

                    // save the connected device's name

                    mConnectedDeviceName = msg.getData().getString(DEVICE_NAME);

                    Toast.makeText(getApplicationContext(), "Connected to "

                            + mConnectedDeviceName, Toast.LENGTH_SHORT).show();

                    break;

                case MESSAGE_TOAST:

                    Toast.makeText(getApplicationContext(), msg.getData().getString(TOAST),

                            Toast.LENGTH_SHORT).show();

                    break;

            }

        }

    };

    private void connectDevice(String addr, boolean secure) {

        System.out.println("connectDevice******************");

        // Get the device MAC address

        String address = addr;

        // Get the BluetoothDevice object

        BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(address);

        // Attempt to connect to the device

        mChatService.connect(device, secure);

    }

    @Override

    public NdefMessage createNdefMessage(NfcEvent event) {

        NdefMessage msg = new NdefMessage(

                new NdefRecord[]{createMime(//the other device recognise this APP and filter a activity by "application/vnd.com.example.huanghanqing.testnfc"

                        "application/vnd.com.example.huanghanqing.testnfcbluetoothchat", mBluetoothAdapter.getAddress().getBytes())

                });

        return msg;

    }

    void processIntent(Intent intent) {

        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

        String bluetoothAddr = new String(msg.getRecords()[0].getPayload());

        connectDevice(bluetoothAddr,false);

    }

}

package com.example.huanghanqing.testnfcbluetoothchat;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import java.util.UUID;

import android.bluetooth.BluetoothAdapter;

import android.bluetooth.BluetoothDevice;

import android.bluetooth.BluetoothServerSocket;

import android.bluetooth.BluetoothSocket;

import android.content.Context;

import android.os.Bundle;

import android.os.Handler;

import android.os.Message;

import android.util.Log;

/**

 * This class does all the work for setting up and managing Bluetooth

 * connections with other devices. It has a thread that listens for

 * incoming connections, a thread for connecting with a device, and a

 * thread for performing data transmissions when connected.

 */

public class BluetoothChatService {

    // Debugging

    private static final String TAG = "BluetoothChatService";

    private static final boolean D = true;

    // Name for the SDP record when creating server socket

    private static final String NAME_SECURE = "BluetoothChatSecure";

    private static final String NAME_INSECURE = "BluetoothChatInsecure";

    // Unique UUID for this application

    private static final UUID MY_UUID_SECURE =

        UUID.fromString("fa87c0d0-afac-11de-8a39-0800200c9a66");

    private static final UUID MY_UUID_INSECURE =

        UUID.fromString("8ce255c0-200a-11e0-ac64-0800200c9a66");

    // Member fields

    private final BluetoothAdapter mAdapter;

    private final Handler mHandler;

    private AcceptThread mSecureAcceptThread;

    private AcceptThread mInsecureAcceptThread;

    private ConnectThread mConnectThread;

    private ConnectedThread mConnectedThread;

    private int mState;

    // Constants that indicate the current connection state

    public static final int STATE_NONE = 0;       // we're doing nothing

    public static final int STATE_LISTEN = 1;     // now listening for incoming connections

    public static final int STATE_CONNECTING = 2; // now initiating an outgoing connection

    public static final int STATE_CONNECTED = 3;  // now connected to a remote device

    /**

     * Constructor. Prepares a new BluetoothChat session.

     * @param context  The UI Activity Context

     * @param handler  A Handler to send messages back to the UI Activity

     */

    public BluetoothChatService(Context context, Handler handler) {

        mAdapter = BluetoothAdapter.getDefaultAdapter();

        mState = STATE_NONE;

        mHandler = handler;

    }

    /**

     * Set the current state of the chat connection

     * @param state  An integer defining the current connection state

     */

    private synchronized void setState(int state) {

        if (D) Log.d(TAG, "setState() " + mState + " -> " + state);

        mState = state;

        // Give the new state to the Handler so the UI Activity can update

        mHandler.obtainMessage(BluetoothChat.MESSAGE_STATE_CHANGE, state, -1).sendToTarget();

    }

    /**

     * Return the current connection state. */

    public synchronized int getState() {

        return mState;

    }

    /**

     * Start the chat service. Specifically start AcceptThread to begin a

     * session in listening (server) mode. Called by the Activity onResume() */

    public synchronized void start() {

        if (D) Log.d(TAG, "start");

        // Cancel any thread attempting to make a connection

        if (mConnectThread != null)

        {

            mConnectThread.cancel();

            mConnectThread = null;

        }

        // Cancel any thread currently running a connection

        if (mConnectedThread != null)

        {

            mConnectedThread.cancel();

            mConnectedThread = null;

        }

        setState(STATE_LISTEN);

        // Start the thread to listen on a BluetoothServerSocket

        if (mSecureAcceptThread == null)

        {

            mSecureAcceptThread = new AcceptThread(true);

            mSecureAcceptThread.start();

        }

        if (mInsecureAcceptThread == null)

        {

            mInsecureAcceptThread = new AcceptThread(false);

            mInsecureAcceptThread.start();

        }

    }

    /**

     * Start the ConnectThread to initiate a connection to a remote device.

     * @param device  The BluetoothDevice to connect

     * @param secure Socket Security type - Secure (true) , Insecure (false)

     */

    public synchronized void connect(BluetoothDevice device, boolean secure) {

        if (D) Log.d(TAG, "connect to: " + device);

        // Cancel any thread attempting to make a connection

        if (mState == STATE_CONNECTING) {

            if (mConnectThread != null) {mConnectThread.cancel(); mConnectThread = null;}

        }

        // Cancel any thread currently running a connection

        if (mConnectedThread != null) {mConnectedThread.cancel(); mConnectedThread = null;}

        // Start the thread to connect with the given device

        mConnectThread = new ConnectThread(device, secure);

        mConnectThread.start();

        setState(STATE_CONNECTING);

    }

    /**

     * Start the ConnectedThread to begin managing a Bluetooth connection

     * @param socket  The BluetoothSocket on which the connection was made

     * @param device  The BluetoothDevice that has been connected

     */

    public synchronized void connected(BluetoothSocket socket, BluetoothDevice

            device, final String socketType) {

        if (D) Log.d(TAG, "connected, Socket Type:" + socketType);

        // Cancel the thread that completed the connection

        if (mConnectThread != null) {mCo
ee5e
nnectThread.cancel(); mConnectThread = null;}

        // Cancel any thread currently running a connection

        if (mConnectedThread != null) {mConnectedThread.cancel(); mConnectedThread = null;}

        // Cancel the accept thread because we only want to connect to one device

        if (mSecureAcceptThread != null) {

            mSecureAcceptThread.cancel();

            mSecureAcceptThread = null;

        }

        if (mInsecureAcceptThread != null) {

            mInsecureAcceptThread.cancel();

            mInsecureAcceptThread = null;

        }

        // Start the thread to manage the connection and perform transmissions

        mConnectedThread = new ConnectedThread(socket, socketType);

        mConnectedThread.start();

        // Send the name of the connected device back to the UI Activity

        Message msg = mHandler.obtainMessage(BluetoothChat.MESSAGE_DEVICE_NAME);

        Bundle bundle = new Bundle();

        bundle.putString(BluetoothChat.DEVICE_NAME, device.getName());

        msg.setData(bundle);

        mHandler.sendMessage(msg);

        setState(STATE_CONNECTED);

    }

    /**

     * Stop all threads

     */

    public synchronized void stop() {

        if (D) Log.d(TAG, "stop");

        if (mConnectThread != null) {

            mConnectThread.cancel();

            mConnectThread = null;

        }

        if (mConnectedThread != null) {

            mConnectedThread.cancel();

            mConnectedThread = null;

        }

        if (mSecureAcceptThread != null) {

            mSecureAcceptThread.cancel();

            mSecureAcceptThread = null;

        }

        if (mInsecureAcceptThread != null) {

            mInsecureAcceptThread.cancel();

            mInsecureAcceptThread = null;

        }

        setState(STATE_NONE);

    }

    /**

     * Write to the ConnectedThread in an unsynchronized manner

     * @param out The bytes to write

     * @see ConnectedThread#write(byte[])

     */

    public void write(byte[] out) {

        // Create temporary object

        ConnectedThread r;

        // Synchronize a copy of the ConnectedThread

        synchronized (this) {

            if (mState != STATE_CONNECTED) return;

            r = mConnectedThread;

        }

        // Perform the write unsynchronized

        r.write(out);

    }

    /**

     * Indicate that the connection attempt failed and notify the UI Activity.

     */

    private void connectionFailed() {

        // Send a failure message back to the Activity

        Message msg = mHandler.obtainMessage(BluetoothChat.MESSAGE_TOAST);//һ��handler�����кܶ�msg

        Bundle bundle = new Bundle();

        bundle.putString(BluetoothChat.TOAST, "Unable to connect device");

        msg.setData(bundle);

        mHandler.sendMessage(msg);

        // Start the service over to restart listening mode

        BluetoothChatService.this.start();

    }

    /**

     * Indicate that the connection was lost and notify the UI Activity.

     */

    private void connectionLost() {

        // Send a failure message back to the Activity

        Message msg = mHandler.obtainMessage(BluetoothChat.MESSAGE_TOAST);

        Bundle bundle = new Bundle();

        bundle.putString(BluetoothChat.TOAST, "Device connection was lost");

        msg.setData(bundle);

        mHandler.sendMessage(msg);

        // Start the service over to restart listening mode

        BluetoothChatService.this.start();

    }

    /**

     * This thread runs while listening for incoming connections. It behaves

     * like a server-side client. It runs until a connection is accepted

     * (or until cancelled).

     */

    private class AcceptThread extends Thread {

        // The local server socket

        private final BluetoothServerSocket mmServerSocket;

        private String mSocketType;

        public AcceptThread(boolean secure) {

            BluetoothServerSocket tmp = null;

            mSocketType = secure ? "Secure":"Insecure";

            // Create a new listening server socket

            try {

                if (secure) {

                    tmp = mAdapter.listenUsingRfcommWithServiceRecord(NAME_SECURE,

                        MY_UUID_SECURE);

                } else {

                    tmp = mAdapter.listenUsingInsecureRfcommWithServiceRecord(

                            NAME_INSECURE, MY_UUID_INSECURE);

                }

            } catch (IOException e) {

                Log.e(TAG, "Socket Type: " + mSocketType + "listen() failed", e);

            }

            mmServerSocket = tmp;

        }

        public void run() {

            if (D) Log.d(TAG, "Socket Type: " + mSocketType +

                    "BEGIN mAcceptThread" + this);

            setName("AcceptThread" + mSocketType);

            BluetoothSocket socket = null;

            // Listen to the server socket if we're not connected

            while (mState != STATE_CONNECTED) {

                try {

                    // This is a blocking call and will only return on a

                    // successful connection or an exception

                    socket = mmServerSocket.accept();

                } catch (IOException e) {

                    Log.e(TAG, "Socket Type: " + mSocketType + "accept() failed", e);

                    break;

                }

                // If a connection was accepted

                if (socket != null) {

                    synchronized (BluetoothChatService.this) {

                        switch (mState) {

                        case STATE_LISTEN:

                        case STATE_CONNECTING:

                            // Situation normal. Start the connected thread.

                            connected(socket, socket.getRemoteDevice(),

                                    mSocketType);

                            break;

                        case STATE_NONE:

                        case STATE_CONNECTED:

                            // Either not ready or already connected. Terminate new socket.

                            try {

                                socket.close();

                            } catch (IOException e) {

                                Log.e(TAG, "Could not close unwanted socket", e);

                            }

                            break;

                        }

                    }

                }

            }

            if (D) Log.i(TAG, "END mAcceptThread, socket Type: " + mSocketType);

        }

        public void cancel() {

            if (D) Log.d(TAG, "Socket Type" + mSocketType + "cancel " + this);

            try {

                mmServerSocket.close();

            } catch (IOException e) {

                Log.e(TAG, "Socket Type" + mSocketType + "close() of server failed", e);

            }

        }

    }

    /**

     * This thread runs while attempting to make an outgoing connection

     * with a device. It runs straight through; the connection either

     * succeeds or fails.

     */

    private class ConnectThread extends Thread {

        private final BluetoothSocket mmSocket;

        private final BluetoothDevice mmDevice;

        private String mSocketType;

        public ConnectThread(BluetoothDevice device, boolean secure) {

            mmDevice = device;

            BluetoothSocket tmp = null;

            mSocketType = secure ? "Secure" : "Insecure";

            // Get a BluetoothSocket for a connection with the

            // given BluetoothDevice

            try {

                if (secure) {

                    tmp = device.createRfcommSocketToServiceRecord(

                            MY_UUID_SECURE);

                } else {

                    tmp = device.createInsecureRfcommSocketToServiceRecord(

                            MY_UUID_INSECURE);

                }

            } catch (IOException e) {

                Log.e(TAG, "Socket Type: " + mSocketType + "create() failed", e);

            }

            mmSocket = tmp;

        }

        public void run() {

            Log.i(TAG, "BEGIN mConnectThread SocketType:" + mSocketType);

            setName("ConnectThread" + mSocketType);

            // Always cancel discovery because it will slow down a connection

            mAdapter.cancelDiscovery();

            // Make a connection to the BluetoothSocket

            try {

                // This is a blocking call and will only return on a

                // successful connection or an exception

                mmSocket.connect();

            } catch (IOException e) {

                // Close the socket

                try {

                    mmSocket.close();

                } catch (IOException e2) {

                    Log.e(TAG, "unable to close() " + mSocketType +

                            " socket during connection failure", e2);

                }

                connectionFailed();

                return;

            }

            // Reset the ConnectThread because we're done

            synchronized (BluetoothChatService.this) {

                mConnectThread = null;

            }

            // Start the connected thread

            connected(mmSocket, mmDevice, mSocketType);

        }

        public void cancel() {

            try {

                mmSocket.close();

            } catch (IOException e) {

                Log.e(TAG, "close() of connect " + mSocketType + " socket failed", e);

            }

        }

    }

    /**

     * This thread runs during a connection with a remote device.

     * It handles all incoming and outgoing transmissions.

     */

    private class ConnectedThread extends Thread {

        private final BluetoothSocket mmSocket;

        private final InputStream mmInStream;

        private final OutputStream mmOutStream;

        public ConnectedThread(BluetoothSocket socket, String socketType) {

            Log.d(TAG, "create ConnectedThread: " + socketType);

            mmSocket = socket;

            InputStream tmpIn = null;

            OutputStream tmpOut = null;

            // Get the BluetoothSocket input and output streams

            try {

                tmpIn = socket.getInputStream();

                tmpOut = socket.getOutputStream();

            } catch (IOException e) {

                Log.e(TAG, "temp sockets not created", e);

            }

            mmInStream = tmpIn;

            mmOutStream = tmpOut;

        }

        public void run() {

            Log.i(TAG, "BEGIN mConnectedThread");

            byte[] buffer = new byte[1024];

            int bytes;

            // Keep listening to the InputStream while connected

            while (true) {

                try {

                    // Read from the InputStream

                    bytes = mmInStream.read(buffer);

                    // Send the obtained bytes to the UI Activity

                    mHandler.obtainMessage(BluetoothChat.MESSAGE_READ, bytes, -1, buffer)

                            .sendToTarget();

                } catch (IOException e) {

                    Log.e(TAG, "disconnected", e);

                    connectionLost();

                    // Start the service over to restart listening mode

                    BluetoothChatService.this.start();

                    break;

                }

            }

        }

        /**

         * Write to the connected OutStream.

         * @param buffer  The bytes to write

         */

        public void write(byte[] buffer) {

            try {

                mmOutStream.write(buffer);

                // Share the sent message back to the UI Activity

                mHandler.obtainMessage(BluetoothChat.MESSAGE_WRITE, -1, -1, buffer)

                        .sendToTarget();

            } catch (IOException e) {

                Log.e(TAG, "Exception during write", e);

            }

        }

        public void cancel() {

            try {

                mmSocket.close();

            } catch (IOException e) {

                Log.e(TAG, "close() of connect socket failed", e);

            }

        }

    }

}