问题
I am getting a issue to send Commands from my android device to Bluetooth device.
Bluetooth is associated with a micro-controller. My effort is below:
public class MainActivity extends AppCompatActivity {
private static final int REQUEST_ENABLE_BT = 2;
private BluetoothAdapter mBluetoothAdapter;
public static final String TAG = "CustomPOC BLEEEEEEE";
private Button btn_send;
private BluetoothDevice mdevice;
private Handler mHandler;
private ConnectThread mConnectThread;
private ConnectedThread mConnectedThread;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
btn_send = (Button)findViewById(R.id.senddata);
if (mBluetoothAdapter == null) {
Toast.makeText(this, "Bluetooth is not available", Toast.LENGTH_LONG).show();
finish();
return;
}
if (!mBluetoothAdapter.isEnabled()) {
Log.i(TAG, "onClick - BT not enabled yet");
Intent enableIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableIntent, REQUEST_ENABLE_BT);
}
pairedOrNot();
btn_send.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
mConnectThread = new ConnectThread(mdevice);
mConnectThread.start();
// new ConnectAsynk(mdevice).execute();
}
});
}
private void pairedOrNot() {
Set<BluetoothDevice> pairedDevices = mBluetoothAdapter.getBondedDevices();
List<String> s = new ArrayList<String>();
for(BluetoothDevice bt : pairedDevices) {
s.add(bt.getAddress());
s.add(bt.getName());
if("08:7C:BE:00:00:01".equals(bt.getAddress())) {
mdevice = bt;
}
}
}
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
switch (requestCode) {
case REQUEST_ENABLE_BT:
// When the request to enable Bluetooth returns
if (resultCode == Activity.RESULT_OK) {
Toast.makeText(this, "Bluetooth has turned on ", Toast.LENGTH_SHORT).show();
} else {
// User did not enable Bluetooth or an error occurred
Log.d(TAG, "BT not enabled");
Toast.makeText(this, "Problem in BT Turning ON ", Toast.LENGTH_SHORT).show();
finish();
}
break;
default:
Log.e(TAG, "wrong request code");
break;
}
}
private class ConnectThread extends Thread {
private final BluetoothSocket mmSocket;
private final BluetoothDevice mmDevice;
private final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805f9b34fb");
public ConnectThread(BluetoothDevice device) {
BluetoothSocket tmp = null;
mmDevice = device;
try {
tmp = device.createInsecureRfcommSocketToServiceRecord(MY_UUID);
/*Method m = mmDevice.getClass().getMethod("createRfcommSocket", new Class[] {int.class});
tmp = (BluetoothSocket) m.invoke(device, 1);*/
System.out.println("BTTTTTTTTTTT Address "+mmDevice.getAddress());
BluetoothDevice hxm = BluetoothAdapter.getDefaultAdapter().getRemoteDevice(mmDevice.getAddress());
// Method m;
// m = hxm.getClass().getMethod("createRfcommSocket", new Class[]{int.class});
// tmp = (BluetoothSocket)m.invoke(hxm, Integer.valueOf(1));
}
catch (Exception e){
e.printStackTrace();
}
mmSocket = tmp;
}
public void run() {
mBluetoothAdapter.cancelDiscovery();
try {
mmSocket.connect();
// Reset the ConnectThread because we're done
synchronized (MainActivity.this) {
mConnectThread = null;
}
// 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;
}
ConnectedThread mConnectedThread = new ConnectedThread(mmSocket);
mConnectedThread.start();
} catch (IOException connectException) {
try {
connectException.printStackTrace();
mmSocket.close();
} catch (IOException closeException) { }
} catch (Exception ex){
ex.printStackTrace();
}
}
public void cancel(){
try {
mmSocket.close();
} catch (IOException e) { e.printStackTrace();}
}
}
private class ConnectedThread extends Thread {
private final BluetoothSocket mmSocket;
private final InputStream mmInStream;
private final OutputStream mmOutStream;
public ConnectedThread(BluetoothSocket socket) {
mmSocket = socket;
InputStream tmpIn = null;
OutputStream tmpOut = null;
try {
tmpIn = socket.getInputStream();
tmpOut = socket.getOutputStream();
} catch (IOException e) { e.printStackTrace();}
mmInStream = tmpIn;
mmOutStream = tmpOut;
}
public void run() {
byte[] buffer = new byte[1024];
int begin = 0;
int bytes = 0;
while (true) {
try {
bytes += mmInStream.read(buffer, bytes, buffer.length - bytes);
for(int i = begin; i < bytes; i++) {
if(buffer[i] == "1010101100000001000000100000000100001110".getBytes()[0]) {
mHandler.obtainMessage(1, begin, i, buffer).sendToTarget();
begin = i + 1;
if(i == bytes - 1) {
bytes = 0;
begin = 0;
}
}
}
} catch (IOException e) {
e.printStackTrace();
break;
}
}
}
public void write(byte[] bytes) {
try {
mmOutStream.write(bytes);
} catch (IOException e) {
e.printStackTrace();
}
}
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
Few heads-up that when i check connection status by
tmp.isConnected()
I found that it is returning a
false
value.
I want to send this command(1010101100000001000000010000000100001110) to external Bluetooth. But i am getting issue. Log trace is below at time launch of application:
08-17 07:48:39.718: W/art(14551): Before Android 4.1, method android.graphics.PorterDuffColorFilter android.support.graphics.
drawable.VectorDrawableCompat.updateTintFilter(android.graphics.PorterDuffColorFilter, android.content.res.ColorStateList,
android.graphics.PorterDuff$Mode) would have incorrectly overridden the package-private method in android.graphics.drawable.Drawable
When click on button btn_send, then i am getting below message in log trace:
08-17 07:51:32.046: W/BluetoothAdapter(14984): getBluetoothService() called with no BluetoothManagerCallback
08-17 07:51:38.448: W/System.err(14984): java.io.IOException: read failed, socket might closed or timeout, read ret: -1
08-17 07:51:38.449: W/System.err(14984): at android.bluetooth.BluetoothSocket.readAll(BluetoothSocket.java:573)
08-17 07:51:38.449: W/System.err(14984): at android.bluetooth.BluetoothSocket.readInt(BluetoothSocket.java:584)
08-17 07:51:38.449: W/System.err(14984): at android.bluetooth.BluetoothSocket.connect(BluetoothSocket.java:321)
08-17 07:51:38.449: W/System.err(14984): at com.mahmad.custompoc11aug.MainActivity$ConnectThread.run(MainActivity.java:164)
and after debug i observe that issue is in this line
mmSocket.connect();
All required permission are given in manifest file.Please help me get rid this issue. Thanks in advance.
回答1:
I tried this library. You can try it also https://github.com/palaima/AndroidSmoothBluetooth
回答2:
I have a very simmilar code and it's working, maybe one of the main differences it that I'm doing a reset of threads:
// Reset the ConnectThread because we're done
synchronized (blablabla.this) {
mConnectThread = null;
}
// 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();
Just after you do:
mmSocket.connect();
hope it helps.
回答3:
As you have mentioned that the issue is there on mmSocket.connect(); line hence, the problem is not while you are sending the command but creating a connection i.e. you are not able to retrieve a BluetoothSocket in opened or connected state.
What should you do ?
Try to use the below code with UUID , its valid for my bluetooth dongles.
UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
createInsecureRfcommSocketToServiceRecord(MY_UUID)
Let me know if this works for you.
Also check, https://stackoverflow.com/a/18786701/1503130
来源：https://stackoverflow.com/questions/38848343/send-command-to-bluetooth-from-android-device