I'm trying to establish a bluetooth connexion between a Samsung Galaxy S3 running with Android 4.0.3 and a RN 42 Bluetooth Chip, here is the model :
I used lot's of different codes for setting up a bluetooth serial communication, and all of them are working very well on the HTC Wildfire i was using before. But now that i'm using the galaxy s3 phone, it's impossible to establish the connexion. Here is the code i'm using, i found it here :
I put the permissions in the android manifest.
First, my Bluetooth Interface :
public class BtInterface {
private BluetoothDevice device = null;
private BluetoothSocket socket = null;
private InputStream receiveStream = null;
private OutputStream sendStream = null;
private ReceiverThread receiverThread;
Handler handler;
public BtInterface(Handler hstatus, Handler h) {
Set<BluetoothDevice> setpairedDevices = BluetoothAdapter.getDefaultAdapter().getBondedDevices();
BluetoothDevice[] pairedDevices = (BluetoothDevice[]) setpairedDevices.toArray(new BluetoothDevice[setpairedDevices.size()]);
for(int i=0;i<pairedDevices.length;i++) {
if(pairedDevices[i].getName().contains("MyBluetoothChip")) {
device = pairedDevices[i];
try {
socket = device.createRfcommSocketToServiceRecord(UUID.fromString("00001101-0000-1000-8000-00805F9B34FB"));
receiveStream = socket.getInputStream();
sendStream = socket.getOutputStream();
} catch (IOException e) {
e.printStackTrace();
}
break;
}
}
handler = hstatus;
receiverThread = new ReceiverThread(h);
}
public void sendData(String data) {
sendData(data, false);
}
public void sendData(String data, boolean deleteScheduledData) {
try {
sendStream.write(data.getBytes());
sendStream.flush();
} catch (IOException e) {
e.printStackTrace();
}
}
public void connect() {
new Thread() {
@Override public void run() {
try {
socket.connect();
Message msg = handler.obtainMessage();
msg.arg1 = 1;
handler.sendMessage(msg);
receiverThread.start();
} catch (IOException e) {
Log.v("N", "Connection Failed : "+e.getMessage());
e.printStackTrace();
}
}
}.start();
}
public void close() {
try {
socket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
public BluetoothDevice getDevice() {
return device;
}
private class ReceiverThread extends Thread {
Handler handler;
ReceiverThread(Handler h) {
handler = h;
}
@Override public void run() {
while(true) {
try {
if(receiveStream.available() > 0) {
byte buffer[] = new byte[100];
int k = receiveStream.read(buffer, 0, 100);
if(k > 0) {
byte rawdata[] = new byte[k];
for(int i=0;i<k;i++)
rawdata[i] = buffer[i];
String data = new String(rawdata);
Message msg = handler.obtainMessage();
Bundle b = new Bundle();
b.putString("receivedData", data);
msg.setData(b);
handler.sendMessage(msg);
}
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
}
Then, my main activity, with just a button to connect and a chat :
public class MonApp extends Activity implements OnClickListener {
private TextView logview;
private EditText sendtext;
private Button connect, send;
private BtInterface bt = null;
private long lastTime = 0;
final Handler handler = new Handler() {
public void handleMessage(Message msg) {
String data = msg.getData().getString("receivedData");
long t = System.currentTimeMillis();
if(t-lastTime > 100) {// Pour Èviter que les messages soit coupÈs
logview.append("\n");
lastTime = System.currentTimeMillis();
}
logview.append(data);
}
};
final Handler handlerStatus = new Handler() {
public void handleMessage(Message msg) {
int co = msg.arg1;
if(co == 1) {
logview.append("Connected\n");
} else if(co == 2) {
logview.append("Disconnected\n");
}
}
};
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
bt = new BtInterface(handlerStatus, handler);
logview = (TextView)findViewById(R.id.logview);
sendtext = (EditText)findViewById(R.id.sendtxt);
connect = (Button)findViewById(R.id.connect);
connect.setOnClickListener(this);
send = (Button)findViewById(R.id.send);
send.setOnClickListener(this);
}
@Override
public void onClick(View v) {
if(v == connect) {
bt.connect();
} else if(v == send) {
bt.sendData(sendtext.getText().toString());
}
}
}
When i try to connect to the chip, this is what i get from the logcat :
09-05 11:37:05.515: I/BluetoothPolicyService(2097): getBluetoothDataTransferAllowed
09-05 11:37:05.520: D/BluetoothPolicyService(2097): MDM: isProfileEnabled = true
09-05 11:37:05.520: D/BluetoothUtils(6868): isSocketAllowedBySecurityPolicy start : device null
09-05 11:37:05.525: V/BluetoothService.cpp(2097): createDeviceNative
09-05 11:37:05.525: V/BluetoothService.cpp(2097): createDeviceNative
09-05 11:37:05.525: V/BluetoothEventLoop.cpp(2097): onCreateDeviceResult
09-05 11:37:05.525: V/BluetoothEventLoop.cpp(2097): onCreateDeviceResult
09-05 11:37:05.525: E/BluetoothEventLoop.cpp(2097): onCreateDeviceResult: D-Bus error: org.bluez.Error.AlreadyExists (Already Exists)
09-05 11:37:05.525: V/BluetoothService.cpp(2097): discoverServicesNative
09-05 11:37:05.525: V/BluetoothService.cpp(2097): ... Object Path = /org/bluez/3094/hci0/dev_00_06_66_43_A1_E6
09-05 11:37:05.525: V/BluetoothService.cpp(2097): ... Pattern = , strlen = 0
09-05 11:37:10.660: V/BluetoothEventLoop.cpp(2097): onDiscoverServicesResult
09-05 11:37:10.660: V/BluetoothEventLoop.cpp(2097): ... Device Path = /org/bluez/3094/hci0/dev_00_06_66_43_A1_E6
09-05 11:37:10.660: E/BluetoothEventLoop.cpp(2097): onDiscoverServicesResult: D-Bus error: org.bluez.Error.ConnectionAttemptFailed (Host is down)
09-05 11:37:10.670: V/N(6868): Connection Failed : Service discovery failed
09-05 11:37:10.670: W/System.err(6868): java.io.IOException: Service discovery failed
09-05 11:37:10.675: W/System.err(6868): at android.bluetooth.BluetoothSocket$SdpHelper.doSdp(BluetoothSocket.java:462)
09-05 11:37:10.675: W/System.err(6868): at android.bluetooth.BluetoothSocket.connect(BluetoothSocket.java:240)
09-05 11:37:10.675: W/System.err(6868): at com.example.bluetooth.BtInterface$1.run(BtInterface.java:68)
I cannot figured out why this code doesn't work with the galaxy s3. I tried to search on google about bluetooth compatibility issues but i didn't find anything so far.
Thank you !
Guillaume
There are plenty of Bluetooth incompatibility issues with the new Android ICS. Apparently they messed around with the Bluetooth code to 'improve security'.
A bug I found and reported(which made my entire embedded board not able to connect for a week with any Android ICS device) was that when establishing a connection to an already paired device, Android ICS would require re-authentication - with or without PIN depends if you use Bluetooth SSP (I use it - this means that for me, on Android ICS connection of 2 bonded devices is still possible without user interaction - but it takes a bit longer).
Please vote this bug on Google Bugtracker - maybe someone will fix it...
Maybe this is your problem as well? Can you specify exactly at what line your code breaks? Surround all your Bluetooth system code with try/catch, etc.
Anyway, the new Bluetooth behavior is very very bad, I heard of a lot of people not being able to connect to their old headset because of it.
Your code seems correct, but as Radu said, the new Bluetooth behaviour si not that good.
I did have quite some troubles myself (with Android 4.1+) and finally used BlueTerm as basis for my app, since it is opensource and is working (at least for the connexion part).
You can find its sources here :
http://pymasde.es/blueterm/
I hope it can help you !
D
来源：https://stackoverflow.com/questions/12274210/android-bluetooth-spp-with-galaxy-s3