I'm trying to connect my Android app with a Bluetooth (classic) peripheral.
After finding the device through a scan, I create a BluetoothSocket without problems. However, mySocket.connect() blocks forever.
public void run(BluetoothAdapter mBluetoothAdapter) {
// Cancel discovery because it otherwise slows down the connection.
mBluetoothAdapter.cancelDiscovery();
try {
// Connect to the remote device through the socket. This call blocks
// until it succeeds or throws an exception.
mySocket.connect();
} catch (IOException connectException) {
// Unable to connect; close the socket and return.
try {
mySocket.close();
} catch (IOException closeException) {
Log.e(TAG, "Could not close the client socket", closeException);
}
return;
}
}
Why a connection timeout error is not thrown?
PS: both my app and the peripheral make use of the default UUID ("00001101-0000-1000-8000-00805F9B34FB"), so this should not be my problem.
I am writing a program for a new vehicle security app. the app allows the user to control lock/unlock operations via his phone app. Lets say the user's phone Bluetooth is switched off at first. If that's the case, when he opens the app, the phone bluetooth adapter should be automatically switched on and should connect with the bluetooth module fixed in to the vehicle.
according to the code I have done, the programatic enabling of the BT adapter of phone works fine. But the connection to the vehicle BT module does NOT happen.
But if the user opens the app while the phone BT adapter is already switched on, then the connection establishing between the vehicle and phone happens automatically.
I need to know why the connection does NOT happen when the BT adapter is turned on programmatically.
Note - the phone and the vehicle BT module is paired. The bluetooth modules mac address is hard coded in the coding.
The coding is as follows. I only pasted the necessary parts. I hope every needed to understand and solve my problem is here. The way I posted the code is pretty messed up. Sorry about that. Hope it's clear. I'm new to this.
private static final UUID MY_UUID =
UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
// Insert bluetooth devices MAC address
private static String address = "00:19:5D:EF:03:79";
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
btAdapter = BluetoothAdapter.getDefaultAdapter();
btAdapter.enable();
#Override
public void onResume() {
super.onResume();
btAdapter.enable();
// Set up a pointer to the remote node using it's address.
BluetoothDevice device = btAdapter.getRemoteDevice(address);
// Two things are needed to make a connection:
// A MAC address, which we got above.
// A Service ID or UUID. In this case we are using the
// UUID for SPP.
try {
btSocket = device.createRfcommSocketToServiceRecord(MY_UUID);
} catch (IOException e) {
errorExit("Fatal Error", "In onResume() and socket create failed: " + e.getMessage() + ".");
}
// Make sure Discovery isn't going on when you attempt to connect and pass your message.
btAdapter.cancelDiscovery();
// Establish the connection. This will block until it connects.
try {
btSocket.connect();
} catch (IOException e) {
try {
btSocket.close();
} catch (IOException e2) {
errorExit("Fatal Error", "In onResume() and unable to close socket during connection failure" + e2.getMessage() + ".");
}
}
// Create a data stream so we can talk to server.
try {
outStream = btSocket.getOutputStream();
} catch (IOException e) {
errorExit("Fatal Error", "In onResume() and output stream creation failed:" + e.getMessage() + ".");
}
}
There might be a timing problem, onCreate and onResume are called in very short order. In the case that the BT is not enabled the code in onResume might be called before the BT service is online.
My advice: Try to delay the initiation a few seconds by putting the code in a Runnable.
private Handler mHandler = new Handler();
public void onCreate() {
[...]
mHandler.postDelayed(new Runnable() {
#Override
public void run() {
btAdapter.enable();
// Set up a pointer to the remote node using it's address.
BluetoothDevice device = btAdapter.getRemoteDevice(address);
// Two things are needed to make a connection:
// A MAC address, which we got above.
// A Service ID or UUID. In this case we are using the
// UUID for SPP.
try {
btSocket = device.createRfcommSocketToServiceRecord(MY_UUID);
} catch (IOException e) {
errorExit("Fatal Error", "In onResume() and socket create failed: " + e.getMessage() + ".");
}
// Make sure Discovery isn't going on when you attempt to connect and pass your message.
btAdapter.cancelDiscovery();
// Establish the connection. This will block until it connects.
try {
btSocket.connect();
} catch (IOException e) {
try {
btSocket.close();
} catch (IOException e2) {
errorExit("Fatal Error", "In onResume() and unable to close socket during connection failure" + e2.getMessage() + ".");
}
}
// Create a data stream so we can talk to server.
try {
outStream = btSocket.getOutputStream();
} catch (IOException e) {
errorExit("Fatal Error", "In onResume() and output stream creation failed:" + e.getMessage() + ".");
}
}, 5000); // 5 second delay
[...]
Caveats: This works really bad if you exit the app promptly after startup. Put the runnable in a member variable and call mHandler.removeCallback(Runnable) in onDestroy().
I'm trying to establish a bluetooth communication between an android phone/tablet (4.0.3), and a bluetooth device, which is an earring reader (Destron Fearring DTR3E, in case you want to know, which I don't suppose you do).
I paired the phone with the reader (the reader has the pairing passcode on a tag) from the bluetooth settings, bluetooth is on of course, and now I'm trying to listen to reads from the device, by means of BluetoothServerSocket. The problem is that the accept call never returns, so obviously I am doing something wrong. The communication is done using RFCOMM.
Code:
private class AcceptThread extends Thread {
private final BluetoothServerSocket mmServerSocket;
public AcceptThread() {
// Use a temporary object that is later assigned to mmServerSocket,
// because mmServerSocket is final
BluetoothServerSocket tmp = null;
try {
// MY_UUID is the app's UUID string, also used by the client code
String uuid = "00001101-0000-1000-8000-00805F9B34FB";
tmp = bluetoothAdapter.listenUsingInsecureRfcommWithServiceRecord("pdfParserServer", UUID.fromString(uuid));
} catch (Exception e) {
e.printStackTrace();
}
mmServerSocket = tmp;
}
public void run() {
BluetoothSocket socket = null;
// Keep listening until exception occurs or a socket is returned
while (true) {
try {
socket = mmServerSocket.accept();
} catch (IOException e) {
break;
}
// If a connection was accepted
if (socket != null) {
// Do work to manage the connection (in a separate thread)
try {
mmServerSocket.close();
} catch (IOException e) {
e.printStackTrace();
}
break;
}
}
}
/** Will cancel the listening socket, and cause the thread to finish */
public void cancel() {
try {
mmServerSocket.close();
} catch (IOException e) { }
}
}
Is there something I am missing?
Thank you!
The only reason that could cause the code never to come back from accept is that, the device "Destron Fearring DTR3E" you are trying to connect to, has actually a bluetoothserver socket and not a bluetooth client, hence, the device might be waiting for you to actually connect to it, in stead of you creating a bluetoothserver socket and waiting for it to connect to your android device, you should read the specs on the device and make sure that actually is you the one that has to open a connection on "Destron Fearring DTR3E" socket...
Hope this helps...
Regards!
I have an Android Bluetooth application which manages a couple of remote devices(Capsules).
Writing data to the socket output stream of a Capsule worked yesterday, and after medium scale refactoring to the Android application only, I get the following error:
java.lang.IllegalMonitorStateException: attempt to unlock read lock, not locked by current thread.
Here is the socket creation code:
public final void connectWithCapsule(Capsule capsule)
throws Exception {
BluetoothSocket socket = capsulesSockets.get(capsule);
if (socket == null) {
try {
// Method m = capsule.getBT_Device().getClass().getMethod("createRfcommSocket", new Class[]{int.class});
// socket = (BluetoothSocket) m.invoke(capsule.getBT_Device(), Integer.valueOf(17));
socket = capsule.getBT_Device().createRfcommSocketToServiceRecord(UUID.fromString("00001101-0000-1000-8000-00805F9B34FB"));
} catch (Exception e) {
logError("Error creating RFcomm socket", e);
throw e;
}
capsulesSockets.put(capsule, socket);
}
try {
socket.connect();
} catch (IOException e) {
logError("Error connecting socket", e);
try {
socket.close();
} catch (IOException e1) {
logError("Error closing socket", e1);
}
capsulesSockets.remove(capsule);
throw e;
}
}
and the model which manages the in/out streams:
public final class KitBT_ConnectionModel {
private final OutputStream[] outputStreams;
private final InputStream[] inputStreams;
public KitBT_ConnectionModel(OutputStream[] outputStreams, InputStream[] inputStreams) {
super();
this.outputStreams = outputStreams;
this.inputStreams = inputStreams;
}
public void transmitData(byte[] bs)
throws IOException {
for (OutputStream outputStream : outputStreams) {
outputStream.write(bs); // THIS LINE THROWS THE EXCEPTION
outputStream.flush();
}
}
public InputStream[] getInputStreams() {
return inputStreams;
}
}
Note: I do not perform any action with both of the streams, and the first write causes the exception.
First thing that pops to mind is which thread puts the read lock and when?
I've tried to play around with the threads which call the socket creation, and the streams transactions, I've made sure, 100% sure they have both been accessed by the same thread (and also tried accessing with different threads), but this exception persists.
Please enlighten me...
HAAAAAAAAAAAAAAAAAAa.........
Darn this LG phones!!!!
I gave the phone a hard reboot, removed the battery and started it over, and it works again...
turning the Bluetooth off and on didn't do the trick! I've been doing it for the past day or so.
God damn it nearly 24 hours of waste for nothing....
How messed up can these products be!
at least it works now!
I'm developing a program in which, from an Android Phone, I have to connect as a client to a Bluetooth medical sensor. I'm using the official Bluetooth API and no problem during connection (SPP profile), but when I end the socket, the sensor is still connected to my phone (although I have close the connection).
Are there any way to make a Bluetooth disconnection? I think there is an intent called ACTION_ACL_CONNECTED, which does that. Can anyone explain me how to use this?
Thanks in advance.
EDITED: Here is the code, if anyone needs additional info, it's a Nonin 4100 medical sensor.
Set<BluetoothDevice> pairedDevices = Activa.myBluetoothAdapter.getBondedDevices();
// If there are paired devices
if (pairedDevices.size() > 0) {
// Loop through paired devices
for (BluetoothDevice device : pairedDevices) {
// Add the name and address to an array adapter to show in a ListView
String name = device.getName();
if (name.contains("Nonin")) {
try {
found = true;
// socket = device.createRfcommSocketToServiceRecord(UUID.fromString("00001101-0000-1000-8000-00805F9B34FB"));
// handler.sendEmptyMessage(5);
// Activa.myBluetoothAdapter.cancelDiscovery();
// socket.connect();
BluetoothDevice hxm = BluetoothAdapter.getDefaultAdapter().getRemoteDevice(device.getAddress());
Method m;
try {
m = hxm.getClass().getMethod("createRfcommSocket", new Class[]{int.class});
socket = (BluetoothSocket)m.invoke(hxm, Integer.valueOf(1));
handler.sendEmptyMessage(5);
socket.connect();
} catch (Exception e) {
handler.sendEmptyMessage(7);
e.printStackTrace();
break;
}
handler.sendEmptyMessage(6);
InputStream in = socket.getInputStream();
OutputStream out = socket.getOutputStream();
byte[] retrieve = { 0x44, 0x31};
out.write(retrieve);
byte [] ack = new byte [1];
in.read(ack);
if (ack[0] == 0x15) {
cancelMeasurement();
return;
}
byte [] data = new byte [3];
long timeStart = System.currentTimeMillis();
this.timePassed = System.currentTimeMillis() - timeStart;
while ((this.timePassed < (this.time))&&(this.finished)) {
try {
in.read(data);
processData(data);
Thread.sleep(1000);
this.timePassed = System.currentTimeMillis() - timeStart;
} catch (Exception e) {
e.printStackTrace();
}
}
in.close();
out.close();
socket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
}
Please remember to close your Input/output streams first, then close the socket.
By closing the streams, you kick off the disconnect process. After you close the socket, the connection should be fully broken down.
If you close the socket before the streams, you may be bypassing certain shutdown steps, such as the (proper) closing of the physical layer connection.
Here's the method I use when its time to breakdown the connection.
/**
* Reset input and output streams and make sure socket is closed.
* This method will be used during shutdown() to ensure that the connection is properly closed during a shutdown.
* #return
*/
private void resetConnection() {
if (mBTInputStream != null) {
try {mBTInputStream.close();} catch (Exception e) {}
mBTInputStream = null;
}
if (mBTOutputStream != null) {
try {mBTOutputStream.close();} catch (Exception e) {}
mBTOutputStream = null;
}
if (mBTSocket != null) {
try {mBTSocket.close();} catch (Exception e) {}
mBTSocket = null;
}
}
EDIT: Adding code for connect():
// bluetooth adapter which provides access to bluetooth functionality.
BluetoothAdapter mBTAdapter = null;
// socket represents the open connection.
BluetoothSocket mBTSocket = null;
// device represents the peer
BluetoothDevice mBTDevice = null;
// streams
InputStream mBTInputStream = null;
OutputStream mBTOutputStream = null;
static final UUID UUID_RFCOMM_GENERIC = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
/**
* Try to establish a connection with the peer.
* This method runs synchronously and blocks for one or more seconds while it does its thing
* SO CALL IT FROM A NON-UI THREAD!
* #return - returns true if the connection has been established and is ready for use. False otherwise.
*/
private boolean connect() {
// Reset all streams and socket.
resetConnection();
// make sure peer is defined as a valid device based on their MAC. If not then do it.
if (mBTDevice == null)
mBTDevice = mBTAdapter.getRemoteDevice(mPeerMAC);
// Make an RFCOMM binding.
try {mBTSocket = mBTDevice.createRfcommSocketToServiceRecord(UUID_RFCOMM_GENERIC);
} catch (Exception e1) {
msg ("connect(): Failed to bind to RFCOMM by UUID. msg=" + e1.getMessage());
return false;
}
msg ("connect(): Trying to connect.");
try {
mBTSocket.connect();
} catch (Exception e) {
msg ("connect(): Exception thrown during connect: " + e.getMessage());
return false;
}
msg ("connect(): CONNECTED!");
try {
mBTOutputStream = mBTSocket.getOutputStream();
mBTInputStream = mBTSocket.getInputStream();
} catch (Exception e) {
msg ("connect(): Error attaching i/o streams to socket. msg=" + e.getMessage());
return false;
}
return true;
}
I found that if I call socket.close() too soon after a recent communication via the OutputStream, then the close fails and I cannot reconnect. I added a Thread.sleep(1000) just prior to the call to close() and this seems to solve it.
HI,
I've seen the exact same problem (HTC Desire).
Despite closing the socket by the book (as Brad suggests), the next connect() blocks forever - until ended by close() by another thread.
I circumvented the problem by always calling BluetoothAdapter.disable()/.enable() before connecting. Awful, unfriendly hack, I know...
I suspect that some of the present BT issues are manufacturer specific, as some app implementors seem to live happily with createRfcommSocketToServiceRecord(), which definitely fails on my HTC Desire (Android 2.1 update 1).
I have seen indications (sorry, don't have references) that HTC Desire's BT stack differs from the Nexus One, although they seem to be very similar devices...
BR
Per
(addition)
Here's a very simple activity to reproduce the problem (without my disable/enable 'cure'):
package com.care2wear.BtTest;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import android.app.Activity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.os.Bundle;
import android.util.Log;
import android.widget.TextView;
public class BtTestActivity extends Activity {
private static final String TAG="BtTest";
BluetoothAdapter mBtAdapter = null;
BluetoothDevice mBtDev = null;
BluetoothSocket mBtSocket = null;
InputStream isBt;
OutputStream osBt;
String mAddress = "00:18:E4:1C:A4:66";
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
init();
connect(); // ok
disconnect(); // ok
connect(); // this invariably fails - blocked until BT is switched off by someone else, or the peer device turns off/goes out of range
disconnect();
}
private void init() {
Log.d(TAG, "initializing");
mBtAdapter = BluetoothAdapter.getDefaultAdapter();
mBtDev = mBtAdapter.getRemoteDevice(mAddress);
Log.d(TAG, "initialized");
}
private void connect() {
try {
Log.d(TAG, "connecting");
Method m = mBtDev.getClass().getMethod("createRfcommSocket", new Class[] { int.class });
mBtSocket = (BluetoothSocket) m.invoke(mBtDev, 1);
mBtSocket.connect();
Log.d(TAG, "connected");
} catch (SecurityException e) {
Log.e(TAG, "SecEx", e);
} catch (NoSuchMethodException e) {
Log.e(TAG, "NsmEx", e);
} catch (IllegalArgumentException e) {
Log.e(TAG, "IArgEx", e);
} catch (IllegalAccessException e) {
Log.e(TAG, "IAccEx", e);
} catch (InvocationTargetException e) {
Log.e(TAG, "ItEx", e);
} catch (IOException e) {
Log.e(TAG, "IOEx", e);
}
}
private void disconnect() {
Log.d(TAG, "closing");
if (isBt != null) {
try {
isBt.close();
} catch (IOException e) {
Log.e(TAG, "isBt IOE", e);
}
isBt = null;
}
if (osBt != null) {
try {
osBt.close();
} catch (IOException e) {
Log.e(TAG, "osBt IOE", e);
}
osBt = null;
}
if (mBtSocket != null) {
try {
mBtSocket.close();
} catch (IOException e) {
Log.e(TAG, "socket IOE", e);
}
mBtSocket = null;
}
Log.d(TAG, "closed");
}
}
If anyone can spot if I'm doing it wrongly, feel free to comment :)
(addition 2)
I think I got it to work now:
The official method of connecting RFCOMM (via SDP) now actually seems to work (HTC Desire, 2.1 update 1), BUT I had to remove and re-pair the BT device. Go figure..
Reconnection may still fail (service discovery failure) if I reconnect 'too quickly' (quit app, then immediately restart). Guess the connection is not completely down yet..
If I always end the (last) activity not only with finish(), but also with Runtime.getRuntime().exit(0);, it works a lot better. Go figure again...
If anyone can explain this, I'll happily learn.
/Per
(addition 3)
Finally got the Froyo (2.2) update for my Desire, and as far as I can see, SPP now works :)
/Per
I was developing an app that conects to a BT device. Your code works fine in my HTC Wildfire but with a Samsung Galaxy I5700 doen't work. Both os are 2.1 update but.....
The exception was 'InvocationTargetException'
The only thing I had to modify is the disconnect().
private void disconnect() {
if(Conectado){
try {
***mBtSocket.close();***
texto.setText(texto.getText()+"\nDesconectado");
Conectado = false;
} catch (IOException e1) {
// TODO Auto-generated catch block
texto.setText(texto.getText()+"\n"+e1.getMessage());
}
catch (Exception e2) {
// TODO Auto-generated catch block
texto.setText(texto.getText()+"\n"+e2.getMessage());
}
}
Hey so I have been using the Bluetooth Chat application from The Android Development site and they provide a stop() method in BluetoothChatService class. So I simply created an instance of it in my main class and and called the stop function from my disconnect button.
Here is how I call it in my main class
// Member object for the chat services
private BluetoothManager mChatService = null;
case R.id.disconnect:
mChatService.stop();
break;
The stop() method in BluetoothChatService
private AcceptThread mAcceptThread;
private ConnectThread mConnectThread;
public synchronized void stop()
{
if (mConnectThread != null)
{
mConnectThread.cancel(); mConnectThread = null;
}
if (mConnectedThread != null)
{
mConnectedThread.cancel(); mConnectedThread = null;
}
if (mAcceptThread != null)
{
mAcceptThread.cancel(); mAcceptThread = null;
}
}
I have the same Issue.
This is the trouble with the Bluetooth Module CSR BC417, present in many devices as serial to bluetooth adapter with SPP profile.
With another Bluetooth module android device works well, and the bluetooth release the conection after the socket is closed,
but with devices with this CSR core not.
Tested on SPP Bluetooth to Serial Adaptor based on CSR BC417, and Bluetooth module from Actisys.
Both with Android 4.0 devices.
I dont know why but is a compatibility issue between harwares, try to change the serial adaptor for another with a different Core.
I tryout programatically to find a solution, even disabling a bluetooth, but is impossible, the trouble is originated on the CSR module.