In my application that in the beginning i only manage a single Activity for connect and exchange data with OBD2 via bluetooth i add a navigation drawer and more tasks that some of them still use bluetooth connection.
For not to weigh bluetooth for each Fragment i close the Socket connection and delete the instantiation of the class MyBluetoothService.java posted below:
public class MyBluetoothService {
// Debugging
private static final String TAG = "MyBluetoothService";
// Unique UUID for this application
private static final UUID MY_UUID_SECURE =
UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
//UUID.fromString("fa87c0d0-afac-11de-8a39-0800200c9a66");
// Member fields
private final BluetoothAdapter mAdapter;
private final Handler mHandler;
//Threads
private ConnectThread mConnectThread;
private ConnectedThread mConnectedThread;
private ManageDataThread mManageThread;
//States UI
private int mState;
private int mNewState;
//Readed Data, raw and formatted
private String rawData = null;
private String formattedMessage = null;
//Stopper for the write array and w8 response
private boolean canGo = true;
private ArrayList<String> commandArray = null;
//private BluetoothSocket mmSocket = null;
//private BluetoothDevice mmDevice = null;
// 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
public static final int STATE_WAIT_RESPONSE = 4; //now wait the response of message send
public static final int STATE_NO_MSG_SEND = 5; //now don't wait for responce
/**
* 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 MyBluetoothService(Context context, Handler handler, ArrayList<String> commands) {
mAdapter = BluetoothAdapter.getDefaultAdapter();
mState = STATE_NONE;
mNewState = mState;
mHandler = handler;
//TODO gestire i comandi direttamente da questa classe con uno sharedArray
commandArray = commands;
}
/**
* Update UI title according to the current state of the chat connection
*/
private synchronized void updateUserInterfaceTitle() {
mState = getState();
Log.d(TAG, "updateUserInterfaceTitle() " + mNewState + " -> " + mState);
mNewState = mState;
// Give the new state to the Handler so the UI Activity can update
mHandler.obtainMessage(Constants.MESSAGE_STATE_CHANGE, mNewState, -1).sendToTarget();
}
/**
* Return the current connection state.
*/
public synchronized int getState() {
return mState;
}
/**
* 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);
// 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;
}
// Cancel any thread currently managing connections
if (mManageThread != null) {
mManageThread.cancel();
mManageThread = null;
}
// Start the thread to connect with the given device
mConnectThread = new ConnectThread(device);
mConnectThread.start();
// Update UI title
updateUserInterfaceTitle();
}
/**
* 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, "manage, Socket Type:");
// 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(socket);
mConnectedThread.start();
// 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);
// Update UI title
updateUserInterfaceTitle();
}
private synchronized void manage(BluetoothSocket socket, BluetoothDevice device) {
Log.d(TAG, "Manage Socket");
// 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 any thread currently managing connections
if (mManageThread != null) {
mManageThread.cancel();
mManageThread = null;
}
canGo = true;
// Start the thread to manage the connection and perform transmissions
mManageThread = new ManageDataThread(socket);
mManageThread.start();
// 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);
// Update UI title
updateUserInterfaceTitle();
}
/**
* 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 (mManageThread != null) {
canGo = false;
mManageThread.cancel();
mManageThread = null;
}
mState = STATE_NONE;
// Update UI title
updateUserInterfaceTitle();
}
/**
* 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(Constants.MESSAGE_TOAST);
Bundle bundle = new Bundle();
bundle.putString(Constants.TOAST, "Unable to connect device");
msg.setData(bundle);
mHandler.sendMessage(msg);
mState = STATE_NONE;
// Update UI title
updateUserInterfaceTitle();
// Start the service over to restart listening mode
MyBluetoothService.this.stop();
}
/**
* 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);
mState = STATE_NONE;
// Update UI title
updateUserInterfaceTitle();
// Start the service over to restart listening mode
//MyBluetoothService.this.start();
}
/**
* 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_SECURE);
} catch (IOException e) {
Log.e(TAG, "Socket Type: create() failed", e);
}
mmSocket = tmp;
mState = STATE_CONNECTING;
}
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) {
// 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 (MyBluetoothService.this) {
mConnectThread = null;
}
// Start the connected thread
//connected(mmSocket, mmDevice);
manage(mmSocket, mmDevice);
Log.d(TAG, "mmSocket: " + mmSocket);
Log.d(TAG, "mmDevice: " + 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;
mState = STATE_CONNECTED;
}
public void run() {
Log.i(TAG, "BEGIN mConnectedThread");
byte[] buffer = new byte[1024];
int bytes;
// Keep listening to the InputStream while connected
while (mState == STATE_CONNECTED) {
try {
// Read from the InputStream
bytes = mmInStream.read(buffer);
//TODO devo gestire l'arrivo di bytes
ObdCommand obc = new ObdCommand();
obc.readResult(mmInStream);
formattedMessage = obc.getResult();
//buffer = (byte) obc.getBuffer();
// Send the obtained bytes to the UI Activity
mHandler.obtainMessage(Constants.MESSAGE_READ, bytes, -1, formattedMessage)
.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(Constants.MESSAGE_WRITE, -1, -1, buffer)
.sendToTarget();
} catch (IOException e) {
Log.e(TAG, "Exception during write", e);
}
}
public void cancel() {
if (mmInStream != null){
try {
mmInStream.close();
} catch (Exception e) {
Log.e(TAG, "close() of InStream socket failed", e);
}
}
if (mmOutStream != null){
try {
mmOutStream.close();
} catch (Exception e) {
Log.e(TAG, "close() of OutStream socket failed", e);
}
}
try {
mmSocket.close();
} catch (IOException e) {
Log.e(TAG, "close() of connect socket failed", e);
}
}
}
/** Thread che controlla la connessione e lo scambio continuo di messaggi con il
* dispositivo OBD connesso ...
*/
//TODO
public class ManageDataThread extends Thread {
private final BluetoothSocket mmSocket;
private final InputStream mmInStream;
private final OutputStream mmOutStream;
private boolean wait_response = false;
private String typeCommand;
public ManageDataThread(BluetoothSocket socket) {
Log.d(TAG, "create ManageDataThread: ");
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;
mState = STATE_CONNECTED;
}
public void run() {
ObdCommand obc = new ObdCommand();
while(canGo) {
for (final String command : commandArray) {
byte[] send = command.getBytes();
write(send); //Setta la wait_response come true
//mState = STATE_WAIT_RESPONSE;
byte[] buffer = new byte[1024];
int bytes;
// Keep listening to the InputStream while connected
while (wait_response) {
try {
// Read from the InputStream
bytes = mmInStream.read(buffer);
obc.readResult(mmInStream);
//formattedMessage = obc.getResult();
formattedMessage = obc.getCalculatedResult();
//Ritorno la ripologia di comando
typeCommand = obc.getCommandType();
//buffer = (byte) obc.getBuffer();
// Send the obtained bytes to the UI Activity
/*mHandler.obtainMessage(Constants.MESSAGE_READ, bytes, -1, formattedMessage)
.sendToTarget();*/
mHandler.obtainMessage(Constants.MESSAGE_READ, bytes, -1, typeCommand
+ ""
+ formattedMessage)
.sendToTarget();
wait_response = false;
} catch (IOException e) {
Log.e(TAG, "disconnected", e);
connectionLost();
break;
}
}
}
try {
ManageDataThread.sleep(400);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
/**
* 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();
wait_response = true;
} catch (IOException e) {
Log.e(TAG, "Exception during write", e);
canGo = false;
}
}
public void cancel() {
try {
canGo = false;
mmSocket.close();
} catch (IOException e) {
Log.e(TAG, "close() of connect socket failed", e);
}
}
}
}
With this class i manage the connection like the BluetoothChatSimple example project.
But in my second fragment i need to connect again to the obd2 and take some particular data. This code is very articulate, there is some better way to do that?
Something that when i change Fragment just stop data exchange from obd and phone but the phone still connected with the obd so in another Fragment i can't send and receive different data by from different Fragments...
PS: I use the manageDataThread for data exchange with obd and get formatted results from hex.
