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error: this class should provide a default constructor (…) [Instantiatable], when creating apk

I am trying to create a signed apk for my application but I get an error after clicking finish after the create a signed apk dialogue.
error: this class should provide a default constructor (…) [Instantiatable]
public class MainActivity {
// 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 = "project";
// Unique UUID for this application
private static final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
// Member fields
private final BluetoothAdapter mAdapter;
private final Handler mHandler;
private AcceptThread mAcceptThread;
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 MainActivity(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
*/
/**
* 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 (mConnectThread != null) {mConnectThread.cancel(); mConnectThread = null;}
// Cancel any thread currently running a connection
if (mConnectedThread != null) {mConnectedThread.cancel(); mConnectedThread = null;}
// Start the thread to listen on a BluetoothServerSocket
if (mAcceptThread == null) {
mAcceptThread = new AcceptThread();
mAcceptThread.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;}
// Start the thread to listen on a BluetoothServerSocket
if (mAcceptThread == null) {
mAcceptThread = new AcceptThread();
mAcceptThread.start();
}
}
/**
* Start the ConnectThread to initiate a connection to a remote device.
* #param device The BluetoothDevice to connect
*/
public synchronized void connect(BluetoothDevice device) {
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);
mConnectThread.start();
}
/**
* 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) {
if (D) Log.d(TAG, "connected");
// Cancel the thread that completed the connection
if (mConnectThread != null) {mConnectThread.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 (mAcceptThread != null) {mAcceptThread.cancel(); mAcceptThread = null;}
// Start the thread to manage the connection and perform transmissions
mConnectedThread = new ConnectedThread(socket);
mConnectedThread.start();
// Send the name of the connected device back to the UI Activity
Message msg = mHandler.obtainMessage(hotlifebluetoothspp.MESSAGE_DEVICE_NAME);
Bundle bundle = new Bundle();
bundle.putString(hotlifebluetoothspp.DEVICE_NAME, device.getName());
msg.setData(bundle);
mHandler.sendMessage(msg);
}
/**
* 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 (mAcceptThread != null) {mAcceptThread.cancel(); mAcceptThread = null;}
}
/**
* 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.
*/
/**
* 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(hotlifebluetoothspp.MESSAGE_TOAST);
Bundle bundle = new Bundle();
bundle.putString(hotlifebluetoothspp.TOAST, "Device connection was lost");
msg.setData(bundle);
mHandler.sendMessage(msg);
}
/**
* 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;
public AcceptThread() {
BluetoothServerSocket tmp = null;
// Create a new listening server socket
try {
tmp = mAdapter.listenUsingRfcommWithServiceRecord(NAME, MY_UUID);
} catch (IOException e) {
Log.e(TAG, "listen() failed", e);
}
mmServerSocket = tmp;
}
public void run() {
if (D) Log.d(TAG, "BEGIN mAcceptThread" + this);
setName("AcceptThread");
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, "accept() failed", e);
break;
}
// If a connection was accepted
if (socket != null) {
synchronized (MainActivity.this) {
switch (mState) {
case STATE_LISTEN:
case STATE_CONNECTING:
// Situation normal. Start the connected thread.
connected(socket, socket.getRemoteDevice());
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");
}
public void cancel() {
if (D) Log.d(TAG, "cancel " + this);
try {
mmServerSocket.close();
} catch (IOException e) {
Log.e(TAG, "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;
public ConnectThread(BluetoothDevice device) {
mmDevice = device;
BluetoothSocket tmp = null;
// Get a BluetoothSocket for a connection with the
// given BluetoothDevice
try {
tmp = device.createRfcommSocketToServiceRecord(MY_UUID);
} catch (IOException e) {
Log.e(TAG, "create() failed", e);
}
mmSocket = tmp;
}
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) {
Log.e(TAG, "close() of connect socket failed", e);
}
}
public BluetoothDevice getMmDevice() {
return mmDevice;
}
}
/**
* 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) {
Log.d(TAG, "create ConnectedThread");
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(hotlifebluetoothspp.MESSAGE_READ, bytes, -1, buffer)
.sendToTarget();
} catch (IOException e) {
Log.e(TAG, "disconnected", e);
connectionLost();
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(hotlifebluetoothspp.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);
}
}
}
}

I would recommend to delete the constructor that you defined and make all initialization during onCreate()method.
Delete this:
public MainActivity(Context context, Handler handler) {
mAdapter = BluetoothAdapter.getDefaultAdapter();
mState = STATE_NONE;
mHandler = handler;
}
And add this:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mAdapter = BluetoothAdapter.getDefaultAdapter();
mState = STATE_NONE;
mHandler = handler;
}
UPDATE
Ericsson
Now I see that your class is not a subclass of Activity. So, MainActivity actually is not an Activity and my suggestion won't work for you.
Usually, we use MainActvity as a subclass of Activity like:
public MainActivity extends Activity {
}
It's hard to tell your intention without more details about you project/code.
Could you please update your question?
If MainActivity is really correct and you really don't want to extends Activity, maybe, the right fix would be just adding the lines below:
public MainActivity() {
}

this class should provide a default constructor (…) [Instantiatable]
Have you tried to add a default constructor?
public MainActivity() {
}

Issue while reading from remote Bluetooth device in Android

I want to read data from a Bluetooth device in my application. In app I show a list of Bluetooth devices available & on clicking on any list item I do like this.
public void onItemClick(AdapterView<?> parent, View view, int position, long id)
{
mBluetoothAdapter.cancelDiscovery();
stopProgressDialog();
String bDevice = (String) mLvDevices.getItemAtPosition(position);
String str = bDevice.substring(bDevice.length() - 17);
BluetoothDevice device = null;
for (int i = 0; i <= mBTDeviceList.size() - 1; i++)
{
if (mBTDeviceList.get(i).getAddress().toString().equalsIgnoreCase(str))
{
device = mBTDeviceList.get(i);
break;
}
}
BluetoothService bluetoothService = new BluetoothService(getActivity(), device);
bluetoothService.connect(device);
}
Following is the BluetoothService class I am using to interact with paired device. I can see in log that I am able to connect with device but when I call read on InputStream object it goes nowhere, it just get stuck there & it shows nothing. I am not getting any clue what is happening there.
Please let me know if anyone has solution for this problem.
public class BluetoothService
{
private static final String TAG = BluetoothService.class.getSimpleName();
private static int MESSAGE_STATE_CHANGE = 4;
// private final BluetoothAdapter mAdapter;
// private final Handler mHandler;
private ConnectThread mConnectThread;
private ConnectedThread mConnectedThread;
private BluetoothDevice mDevice;
private int mState;
private static final UUID SerialPortServiceClass_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
private static final boolean D = true;
public static final int STATE_NONE = 0;
public static final int STATE_LISTEN = 1;
public static final int STATE_CONNECTING = 2;
public static final int STATE_CONNECTED = 3;
/****
* 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 BluetoothService(Context context, BluetoothDevice device)
{
this.mState = STATE_NONE;
this.mDevice = device;
}
/****
* 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(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_NONE);
}
/**
* Start the ConnectThread to initiate a connection to a remote device.
*
* #param device
* The BluetoothDevice to connect
*/
public synchronized void connect(BluetoothDevice device)
{
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);
mConnectThread.start();
setState(STATE_CONNECTING);
}
/**
* Start the ConnectedThread to begin managing a Bluetooth connection
*/
public synchronized void connected(android.bluetooth.BluetoothSocket mmSocket, BluetoothDevice device)
{
if (D)
Log.d(TAG, "connected");
/* Cancel the thread that completed the connection */
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 manage the connection and perform transmissions */
mConnectedThread = new ConnectedThread(mmSocket);
mConnectedThread.start();
/* Send the name of the connected device back to the UI Activity */
}
/**
* 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;
}
setState(STATE_NONE);
}
/**
* Write to the ConnectedThread in an unsynchronized manner
*/
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()
{
setState(STATE_NONE);
/* Send a failure message back to the Activity */
}
/**
* 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 android.bluetooth.BluetoothSocket mmSocket;
private final BluetoothDevice mmDevice;
public ConnectThread(BluetoothDevice device)
{
mmDevice = device;
android.bluetooth.BluetoothSocket tmp = null;
/*
* Get a BluetoothSocket for a connection with the given
* BluetoothDevice
*/
try
{
tmp = device.createRfcommSocketToServiceRecord(SerialPortServiceClass_UUID);
} catch (IOException e)
{
Log.e(TAG, "create() failed", e);
}
mmSocket = tmp;
}
public void run()
{
Log.i(TAG, "BEGIN mConnectThread");
setName("ConnectThread");
/* 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)
{
connectionFailed();
/* Close the socket */
try
{
mmSocket.close();
} catch (IOException e2)
{
Log.e(TAG, "unable to close() socket during connection failure", e2);
}
// Start the service over to restart listening mode
return;
}
/* Reset the ConnectThread because we're done */
synchronized (BluetoothService.this)
{
mConnectThread = null;
}
/* Start the connected thread */
connected(mmSocket, mmDevice);
}
public void cancel()
{
try
{
mmSocket.close();
} catch (IOException e)
{
Log.e(TAG, "close() of connect 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
{
byte[] buffer = new byte[1];
private final BluetoothSocket mmSocket;
private final OutputStream mmOutStream;
private final InputStream mmInStream;
public ConnectedThread(android.bluetooth.BluetoothSocket mmSocket2)
{
Log.d(TAG, "create ConnectedThread");
mmSocket = mmSocket2;
InputStream tmpIn = null;
BufferedOutputStream tmpOut = null;
/* Get the BluetoothSocket input and output streams */
try
{
Log.i(TAG, "input and outstreams");
tmpIn = mmSocket2.getInputStream();
// tmpOut = mmSocket2.getOutputStream();
tmpOut = new BufferedOutputStream(mmSocket.getOutputStream());
} catch (IOException e)
{
Log.e(TAG, "temp sockets not created", e);
}
mmInStream = tmpIn;
mmOutStream = tmpOut;
}
public void run()
{
int bytes = 0;
Log.i(TAG, "Starting Connected Thread");
/* Keep listening to the InputStream while connected */
while (true)
{
try
{
Log.i(TAG, "mmInStream available: " + mmInStream.available());
byte[] buffer = new byte[1024];
bytes = mmInStream.read(buffer);// , 0, buffer.length);
Log.i(TAG, "read in buffer: " + buffer.toString());
} catch (IOException e)
{
Log.e(TAG, "disconnected", e);
break;
}
}
}
public void write(byte[] bytes)
{
try
{
mmOutStream.write(bytes);
} catch (IOException e)
{
}
}
public void cancel()
{
try
{
mmSocket.close();
} catch (IOException e)
{
Log.e(TAG, "close() of connect socket failed", e);
}
}
}
}

Make sure that you're sending data for the InputBuffer to read. The read() method blocks the thread until something has been read

I had a similar issue, that was resolved after a workaround on the socket creation. Apart from this, I have the class exactly the same than you in an app that works.
private class ConnectThread extends Thread {
private final BluetoothSocket mmSocket;
private final BluetoothDevice mmDevice;
public ConnectThread(BluetoothDevice device) throws IOException {
mmDevice = device;
BluetoothSocket tmp = null;
Method m = null;
try {
m = device.getClass().getMethod("createRfcommSocket", new Class[] { int.class });
} catch (NoSuchMethodException e) {
e.printStackTrace();
}
try {
tmp = (BluetoothSocket) m.invoke(device, Integer.valueOf(1));
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (IllegalArgumentException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
}
mmSocket = tmp;
}
}

Null pointer exception while sending message

I build android app voice recognition command to control devices over embedded bluetooth, i use example code BluetoothChat to send voice recognition result. but i got an error like this.
enter FATAL EXCEPTION: main
java.lang.RuntimeException: Failure delivering result ResultInfo{who=null, request=100, result=-1, data=Intent { (has extras) }} to activity {com.embox.rumahpintar/com.embox.rumahpintar.MainActivity}: java.lang.NullPointerException
at android.app.ActivityThread.deliverResults(ActivityThread.java:3378)
at android.app.ActivityThread.handleSendResult(ActivityThread.java:3421)
at android.app.ActivityThread.access$1100(ActivityThread.java:148)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1311)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:5162)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:756)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:572)
at miui.dexspy.DexspyInstaller.main(DexspyInstaller.java:171)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.NullPointerException
at com.embox.rumahpintar.MainActivity.sendMessage(MainActivity.java:102)
at com.embox.rumahpintar.MainActivity.onActivityResult(MainActivity.java:89)
at android.app.Activity.dispatchActivityResult(Activity.java:5324)
at android.app.ActivityThread.deliverResults(ActivityThread.java:3374)
at android.app.ActivityThread.access$1100(ActivityThread.java:148)
            
this is MainActivity class:
public class MainActivity extends ActionBarActivity {
private static final String TAG = "voice";
private final int REQ_CODE_SPEECH_INPUT = 100;
private TextView speakInput;
ArrayList<String> result;
Button tapSpeak;
String perintah = "hidupkan lampu kamar";
BluetoothService mService = null;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if (savedInstanceState == null) {
FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
BluetoothFragment fragment = new BluetoothFragment();
transaction.replace(R.id.sample_content_fragment, fragment);
transaction.commit();
}
Toast.makeText(this, "Smart Home #Created by Akmal Fadli", Toast.LENGTH_LONG).show();
speakInput = (TextView) findViewById(R.id.speakInput);
tapSpeak = (Button) findViewById(R.id.tapSpeak);
tapSpeak.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Log.i(TAG, "Speak recognition open....");
promptSpeechInput();
}
});
}
public void promptSpeechInput() {
Intent intent = new Intent(RecognizerIntent.ACTION_RECOGNIZE_SPEECH);
intent.putExtra(RecognizerIntent.EXTRA_LANGUAGE_MODEL,
RecognizerIntent.LANGUAGE_MODEL_FREE_FORM);
intent.putExtra(RecognizerIntent.EXTRA_LANGUAGE, Locale.getDefault());
intent.putExtra(RecognizerIntent.EXTRA_PROMPT,
getString(R.string.speech_prompt));
try {
startActivityForResult(intent, REQ_CODE_SPEECH_INPUT);
} catch (ActivityNotFoundException a) {
Toast.makeText(getApplicationContext(),
getString(R.string.speech_not_supported),
Toast.LENGTH_SHORT).show();
}
}
/**
* Receiving speech input
*/
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
switch (requestCode) {
case REQ_CODE_SPEECH_INPUT: {
if (resultCode == RESULT_OK && null != data) {
result = data
.getStringArrayListExtra(RecognizerIntent.EXTRA_RESULTS);
speakInput.setText(result.get(0));
BluetoothFragment m = new BluetoothFragment();
if (result.contains(perintah)) {
Toast.makeText(this, "Perintah terkirim . . .", Toast.LENGTH_LONG).show();
sendMessage(perintah);
}
break;
}
}
}
}
private void sendMessage(String message) {
// Check that we're actually connected before trying anything
if (mService.getState() != BluetoothService.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();
mService.write(send);
}
}
And this is SendMessage method:
public void sendMessage(String message) {
// Check that we're actually connected before trying anything
if (mService.getState() != BluetoothService.STATE_CONNECTED) {
Toast.makeText(getActivity(), 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();
mService.write(send);
}
}
give me advice please . . .
BluetoothService Class:
public class BluetoothService {
// Debugging
private static final String TAG = "BluetoothChatService";
// Name for the SDP record when creating server socket
private static final String NAME_INSECURE = "BluetoothChatInsecure";
// Unique UUID for this application
private static final UUID MY_UUID_SECURE = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
//UUID uuid = device.getUuids()[0].getUuid();
//MY_UUID_SECURE = uuid;
// 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 BluetoothService(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) {
Log.d(TAG, "setState() " + mState + " -> " + state);
mState = state;
// Give the new state to the Handler so the UI Activity can update
mHandler.obtainMessage(Constants.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() {
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
*
*/
public synchronized void connect(BluetoothDevice device) {
Log.d(TAG, "connect to: " + device);
mAdapter.cancelDiscovery();
// 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);
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) {
// Log.d(TAG, "connected, Socket Type:" + socketType);
// Cancel the thread that completed the connection
if (mConnectThread != null) {
mConnectThread.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);
mConnectedThread.start();
String konek = "Device connected...";
byte[] pesan = konek.getBytes();
mConnectedThread.write(pesan);
// Send the name of the connected device back to the UI Activity
Message msg = mHandler.obtainMessage(Constants.MESSAGE_DEVICE_NAME);
Bundle bundle = new Bundle();
bundle.putString(Constants.DEVICE_NAME, device.getName());
msg.setData(bundle);
mHandler.sendMessage(msg);
setState(STATE_CONNECTED);
}
/**
* Stop all threads
*/
public synchronized void stop() {
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[]) (java.lang.String)
*/
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(Constants.MESSAGE_TOAST);
Bundle bundle = new Bundle();
bundle.putString(Constants.TOAST, "Unable to connect device");
msg.setData(bundle);
mHandler.sendMessage(msg);
// Start the service over to restart listening mode
// BluetoothService.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(Constants.MESSAGE_TOAST);
Bundle bundle = new Bundle();
bundle.putString(Constants.TOAST, "Device connection was lost");
msg.setData(bundle);
mHandler.sendMessage(msg);
// Start the service over to restart listening mode
//BluetoothService.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 {
tmp = mAdapter.listenUsingInsecureRfcommWithServiceRecord(
NAME_INSECURE, MY_UUID_SECURE);
} catch (IOException e) {
Log.e(TAG, "Socket Type: " + mSocketType + "listen() failed", e);
}
mmServerSocket = tmp;
}
public void run() {
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 (BluetoothService.this) {
switch (mState) {
case STATE_LISTEN:
case STATE_CONNECTING:
// Situation normal. Start the connected thread.
connected(socket, socket.getRemoteDevice());
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;
}
}
}
}
Log.i(TAG, "END mAcceptThread, socket Type: " + mSocketType);
}
public void cancel() {
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;
public ConnectThread(BluetoothDevice device) {
mmDevice = device;
BluetoothSocket tmp = null;
// mSocketType = secure ? "Secure" : "Insecure";
// Get a BluetoothSocket for a connection with the
// given BluetoothDevice
try {
tmp = device.createRfcommSocketToServiceRecord(
MY_UUID_SECURE);
} catch (IOException e) {
Log.e(TAG, "Socket Type: " + "create() failed", e);
}
mmSocket = tmp;
}
public void run() {
// 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() " +
" socket during connection failure", e2);
}
connectionFailed();
return;
}
// Reset the ConnectThread because we're done
synchronized (BluetoothService.this) {
mConnectThread = null;
}
// Start the connected thread
connected(mmSocket, mmDevice);
}
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) {
Log.e(TAG, "close() of connect " + " socket failed", e);
}
}
}
/**
* This thread runs during a connection with a remote device.
* It handles all incoming and outgoing transmissions.
*/
//public class dulunya private
private class ConnectedThread extends Thread {
private final BluetoothSocket mmSocket;
private final InputStream mmInStream;
private final OutputStream mmOutStream;
public ConnectedThread(BluetoothSocket socket) {
// 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(Constants.MESSAGE_READ, bytes, -1, buffer)
.sendToTarget();
} catch (IOException e) {
Log.e(TAG, "disconnected", e);
connectionLost();
// Start the service over to restart listening mode
BluetoothService.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(Constants.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);
}
}
}
SOLVED, I modified my code into one activity (MainActivity.class), so i moved BluetoothService into MainActivity.

You never initialize kirimPesan so it has null value. So you have NullPointerException (exception that tells you that something is null).
You need to initialize kirimPesan with constructor before you able to send messages.
Alternatively you can put method sendMessage in your own class MainActivity, then you will not need kirimPesan object at all.

How to send same message one by one to a multiple device via bluetooth in android?

I have list of bluetooth device i just want to send a same message to each device one by one via bluetooth.But at this work i stuck.I am confuse to resolve this problem. Please help..Thanks in advance.. My code snippet is below:
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 = "BluetoothChat";
// Unique UUID for this application
private static final UUID MY_UUID = UUID.fromString("fa87c0d0-afac-11de-8a39-0800200c9a66");
// Member fields
private final BluetoothAdapter mAdapter;
private final Handler mHandler;
private AcceptThread mAcceptThread;
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;}
// Start the thread to listen on a BluetoothServerSocket
if (mAcceptThread == null) {
mAcceptThread = new AcceptThread();
mAcceptThread.start();
}
setState(STATE_LISTEN);
}
/**
* Start the ConnectThread to initiate a connection to a remote device.
* #param device The BluetoothDevice to connect
*/
public synchronized void connect(BluetoothDevice device) {
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);
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) {
if (D) Log.d(TAG, "connected");
// Cancel the thread that completed the connection
if (mConnectThread != null) {mConnectThread.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 (mAcceptThread != null) {mAcceptThread.cancel(); mAcceptThread = null;}
// Start the thread to manage the connection and perform transmissions
mConnectedThread = new ConnectedThread(socket);
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 (mAcceptThread != null) {mAcceptThread.cancel(); mAcceptThread = 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() {
setState(STATE_LISTEN);
// Send a failure message back to the Activity
Message msg = mHandler.obtainMessage(BluetoothChat.MESSAGE_TOAST);
Bundle bundle = new Bundle();
bundle.putString(BluetoothChat.TOAST, "Unable to connect device");
msg.setData(bundle);
mHandler.sendMessage(msg);
}
/**
* Indicate that the connection was lost and notify the UI Activity.
*/
private void connectionLost() {
setState(STATE_LISTEN);
// 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);
}
/**
* 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;
public AcceptThread() {
BluetoothServerSocket tmp = null;
// Create a new listening server socket
try {
tmp = mAdapter.listenUsingInsecureRfcommWithServiceRecord(NAME, MY_UUID);
} catch (IOException e) {
Log.e(TAG, "listen() failed", e);
}
mmServerSocket = tmp;
}
public void run() {
if (D) Log.d(TAG, "BEGIN mAcceptThread" + this);
setName("AcceptThread");
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, "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());
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");
}
public void cancel() {
if (D) Log.d(TAG, "cancel " + this);
try {
mmServerSocket.close();
} catch (IOException e) {
Log.e(TAG, "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;
public ConnectThread(BluetoothDevice device) {
mmDevice = device;
BluetoothSocket tmp = null;
// Get a BluetoothSocket for a connection with the
// given BluetoothDevice
try {
tmp = device.createInsecureRfcommSocketToServiceRecord(MY_UUID);
} catch (IOException e) {
Log.e(TAG, "create() failed", e);
}
mmSocket = tmp;
}
public void run() {
Log.i(TAG, "BEGIN mConnectThread");
setName("ConnectThread");
// 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) {
connectionFailed();
// Close the socket
try {
mmSocket.close();
} catch (IOException e2) {
Log.e(TAG, "unable to close() socket during connection failure", e2);
}
// Start the service over to restart listening mode
BluetoothChatService.this.start();
return;
}
// Reset the ConnectThread because we're done
synchronized (BluetoothChatService.this) {
mConnectThread = null;
}
// Start the connected thread
connected(mmSocket, mmDevice);
}
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) {
Log.e(TAG, "close() of connect 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) {
Log.d(TAG, "create ConnectedThread");
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();
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);
}
}
}
}
/**
* This is the main Activity that displays the current chat session.
*/
public class BluetoothChat extends Activity {
// Debugging
private static final String TAG = "BluetoothChat";
private static final boolean D = true;
public static String EXTRA_DEVICE_ADDRESS = "device_address";
// 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;
private ArrayList<String> visible;
// 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 = 1;
private static final int REQUEST_ENABLE_BT = 2;
// Layout Views
private TextView mTitle;
private ListView mConversationView;
private EditText mOutEditText;
private Button mSendButton;
private String username = "";
private String data = "";
private int count = 0;
private int visible_length;
public String message="jsjasg" ;
// 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;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (D)
Log.e(TAG, "+++ ON CREATE +++");
// Set up the window layout
// requestWindowFeature(Window.FEATURE_CUSTOM_TITLE);
// getWindow().setFeatureInt(Window.FEATURE_CUSTOM_TITLE,
// R.layout.custom_title);
setContentView(R.layout.main);
// Set up the custom title
// mTitle = (TextView) findViewById(R.id.title_left_text);
// mTitle.setText(R.string.app_name);
// mTitle = (TextView) findViewById(R.id.title_right_text);
// 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;
}
}
#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()) {
Intent enableIntent = new Intent(
BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableIntent, REQUEST_ENABLE_BT);
// Otherwise, setup the chat session
} else {
if (mChatService == null)
setupChat();
}
}
#Override
public synchronized void onResume() {
super.onResume();
if (D)
Log.e(TAG, "+ ON RESUME +");
// 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
//connect();
mChatService.start();
}
}
}
private void setupChat() {
Log.d(TAG, "setupChat()");
// Initialize the array adapter for the conversation thread
Set<BluetoothDevice> pairedDevices = mBluetoothAdapter
.getBondedDevices();
// If there are paired devices, add each one to the ArrayAdapter
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);
message = view.getText.toString();
sendMessage(message);
}
});
// Initialize the BluetoothChatService to perform bluetooth connections
mChatService = new BluetoothChatService(this, mHandler);
// Initialize the buffer for outgoing messages
mOutStringBuffer = new StringBuffer("");
}
#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();
System.out.println("one two");
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);
try {
JSONObject jsobj = new JSONObject(mOutStringBuffer.toString());
JSONArray json = jsobj.getJSONArray("login");
JSONObject _json = json.getJSONObject(0);
username = _json.getString("username");
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
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;
}
};
// 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:
// mTitle.setText(R.string.title_connected_to);
// mTitle.append(mConnectedDeviceName);
mConversationArrayAdapter.clear();
break;
case BluetoothChatService.STATE_CONNECTING:
// mTitle.setText(R.string.title_connecting);
break;
case BluetoothChatService.STATE_LISTEN:
case BluetoothChatService.STATE_NONE:
// mTitle.setText(R.string.title_not_connected);
connect();
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);
System.out.println("abcdefghijklmnopqrst");
//connect();
break;
case MESSAGE_READ:
byte[] readBuf = (byte[]) msg.obj;
// construct a string from the valid bytes in the buffer
System.out.println("length"+readBuf.length);
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;
}
}
};
public void onActivityResult(int requestCode, int resultCode, Intent data) {
if (D)
Log.d(TAG, "onActivityResult " + resultCode);
switch (requestCode) {
case REQUEST_CONNECT_DEVICE:
// When DeviceListActivity returns with a device to connect
if (resultCode == Activity.RESULT_OK) {
// Get the device MAC address
visible=new ArrayList<String>();
visible=data.getExtras().getStringArrayList("device");
String address = data.getExtras().getString(
DeviceListActivity.EXTRA_DEVICE_ADDRESS);
count=0;
// Get the BLuetoothDevice object
BluetoothDevice device = mBluetoothAdapter
.getRemoteDevice(address);
// pairDevice(device);
// Attempt to connect to the device
mChatService.connect(device);
}
break;
case REQUEST_ENABLE_BT:
// When the request to enable Bluetooth returns
if (resultCode == Activity.RESULT_OK) {
// Bluetooth is now enabled, so set up a chat session
setupChat();
} else {
// User did not enable Bluetooth or an error occured
Log.d(TAG, "BT not enabled");
Toast.makeText(this, R.string.bt_not_enabled_leaving,
Toast.LENGTH_SHORT).show();
finish();
}
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.option_menu, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.scan:
// Launch the DeviceListActivity to see devices and do scan
Intent serverIntent = new Intent(this, DeviceListActivity.class);
startActivityForResult(serverIntent, REQUEST_CONNECT_DEVICE);
return true;
case R.id.discoverable:
// Ensure this device is discoverable by others
ensureDiscoverable();
return true;
}
return false;
}
}
}
DeviceListActivity:
This activity is use to get all nearest android device mac address.

Android, exchange information after Bluetooth pairing with authentication only //

i want to exchange some information via Bluetooth with pairing of 2 android devices with authentication only.. i have seen the android chat sample example available in android developer side ..its work well but now i want after Bluetooth pairing of 2 devices , want to exchange some information to each other as when a device send its some information to other devise a authentication pop up would be appear to remote device and if it accepted then only share information to other side...vv thanks in adv....
using below code i also want to show authentication before pairing 2 devices via Bluetooth..but it directly pair without any authentication send to other side
code for BluetoothChatService.jave taken from android developer side is below
public class BluetoothChatService extends Activity {
// 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 = "BluetoothChat";
// Unique UUID for this application
private static final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
// ("fa87c0d0-afac-11de-8a39-0800200c9a66");
// Member fields
private final BluetoothAdapter mAdapter;
private final Handler mHandler;
private AcceptThread mAcceptThread;
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;
}
// Start the thread to listen on a BluetoothServerSocket
if (mAcceptThread == null) {
mAcceptThread = new AcceptThread();
mAcceptThread.start();
}
setState(STATE_LISTEN);
}
/**
* Start the ConnectThread to initiate a connection to a remote device.
*
* #param device
* The BluetoothDevice to connect
*/
public synchronized void connect(BluetoothDevice device) {
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);
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) {
if (D) {
Log.d(TAG, "connected");
}
// Cancel the thread that completed the connection
if (mConnectThread != null) {
mConnectThread.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 (mAcceptThread != null) {
mAcceptThread.cancel();
mAcceptThread = null;
}
// Start the thread to manage the connection and perform transmissions
mConnectedThread = new ConnectedThread(socket);
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 (mAcceptThread != null) {
mAcceptThread.cancel();
mAcceptThread = 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() {
setState(STATE_LISTEN);
// Send a failure message back to the Activity
Message msg = mHandler.obtainMessage(BluetoothChat.MESSAGE_TOAST);
Bundle bundle = new Bundle();
bundle.putString(BluetoothChat.TOAST, "Unable to connect device");
msg.setData(bundle);
mHandler.sendMessage(msg);
}
/**
* Indicate that the connection was lost and notify the UI Activity.
*/
private void connectionLost() {
setState(STATE_LISTEN);
// 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);
}
/**
* 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;
public AcceptThread() {
BluetoothServerSocket tmp = null;
// Create a new listening server socket
try {
tmp = mAdapter
.listenUsingRfcommWithServiceRecord(NAME, MY_UUID);
// if(!tmp.toString().equalsIgnoreCase(null)){
//
// }
} catch (IOException e) {
Log.e(TAG, "listen() failed", e);
}
mmServerSocket = tmp;
}
#Override
public void run() {
if (D) {
Log.d(TAG, "BEGIN mAcceptThread" + this);
}
setName("AcceptThread");
BluetoothSocket socket = null;
// Listen to the server socket if we're not connected
while (mState != STATE_CONNECTED) {
try {
socket = mmServerSocket.accept();
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
// 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());
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");
}
}
public void cancel() {
if (D) {
Log.d(TAG, "cancel " + this);
}
try {
mmServerSocket.close();
} catch (IOException e) {
Log.e(TAG, "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;
public ConnectThread(BluetoothDevice device) {
mmDevice = device;
BluetoothSocket tmp = null;
try {
try {
tmp = device.createRfcommSocketToServiceRecord(MY_UUID);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
} catch (SecurityException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
mmSocket = tmp;
}
#Override
public void run() {
Log.i(TAG, "BEGIN mConnectThread");
setName("ConnectThread");
// 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) {
connectionFailed();
// Close the socket
try {
mmSocket.close();
} catch (IOException e2) {
Log.e(TAG,"unable to close() socket during connection failure",
e2);
}
// Start the service over to restart listening mode
BluetoothChatService.this.start();
return;
}
// Reset the ConnectThread because we're done
synchronized (BluetoothChatService.this) {
mConnectThread = null;
}
// Start the connected thread
connected(mmSocket, mmDevice);
}
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) {
Log.e(TAG, "close() of connect 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) {
Log.d(TAG, "create ConnectedThread");
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;
}
#Override
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
// XXX !!!
String buffer2 = new String(buffer);
buffer2= buffer2.substring(0, buffer2.length()-3)+"\n";
mHandler.obtainMessage(BluetoothChat.MESSAGE_READ, bytes,
-1, buffer2.getBytes()).sendToTarget();
} catch (IOException e) {
Log.e(TAG, "disconnected", e);
connectionLost();
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
// XXX !!!
String buffer2 = new String(buffer);
buffer2= buffer2.substring(0, buffer2.length()-2);
mHandler.obtainMessage(BluetoothChat.MESSAGE_WRITE, -1, -1,
buffer2.getBytes()).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);
}
}
}