问题
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
回答1:
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.
回答2:
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