Get address of connected device bluetooth

[shlokj]

I'm working on an application to send data over bluetooth to the connected device. For reference, I copied code from the Google sample, and I have this code:

package in.justrobotics.jrbluetoothcontrol;

import android.Manifest;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothProfile;
import android.bluetooth.BluetoothSocket;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.pm.PackageManager;
import android.os.Bundle;
import android.os.Handler;
import android.os.SystemClock;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.MotionEvent;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

import java.io.IOException;
import java.io.InputStream;
import java.io_OutputStream;
import java.io.UnsupportedEncodingException;
import java.lang.reflect.Method;
import java.util.Set;
import java.util.UUID;

public class ControllerActivity extends AppCompatActivity {

// GUI Components
// private TextView mBluetoothStatus;
// private TextView mReadBuffer;
// private Button mScanBtn;
// private Button mOffBtn;
// private Button mListPairedDevicesBtn;
// private Button mDiscoverBtn;
private BluetoothAdapter mBTAdapter;
private Set<BluetoothDevice> mPairedDevices;
private ArrayAdapter<String> mBTArrayAdapter;
private ListView mDevicesListView;
private ImageView Up,Down,Left,Right;
private int commandFromForward,commandFromReverse,commandFromLeft,commandFromRight;
private final String TAG = MainActivity.class.getSimpleName();
private Handler mHandler; // Our main handler that will receive callback notifications
private ConnectedThread mConnectedThread; // bluetooth background worker thread to send and receive data
private BluetoothSocket mBTSocket = null; // bi-directional client-to-client data path

private static final UUID BTMODULEUUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB"); // "random" unique identifier


// #defines for identifying shared types between calling functions
private final static int REQUEST_ENABLE_BT = 1; // used to identify adding bluetooth names
private final static int MESSAGE_READ = 2; // used in bluetooth handler to identify message update
private final static int CONNECTING_STATUS = 3; // used in bluetooth handler to identify message status
public String rBTaddress;
public String rBTname;


@override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_controller);
Up = (ImageView) findViewById(R.id.upfwd);
Down = (ImageView) findViewById(R.id.downbk);
Left = (ImageView) findViewById(R.id.leftlt);
Right = (ImageView) findViewById(R.id.rightrt);
commandFromForward=0;
commandFromReverse=0;
commandFromLeft=0;
commandFromRight=0;

// mDevicesListView = (ListView)findViewById(R.id.devicesListView);
// mDevicesListView.setAdapter(mBTArrayAdapter); // assign model to view
// mDevicesListView.setOnItemClickListener(mDeviceClickListener);
mBTArrayAdapter = new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1);

// Ask for location permission if not already allowed
if(ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED)
ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.ACCESS_COARSE_LOCATION}, 1);


mHandler = new Handler(){
public void handleMessage(android.os.Message msg){
if(msg.what == MESSAGE_READ){
String readMessage = null;
try {
readMessage = new String((byte[]) msg.obj, "UTF-8");
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
// mReadBuffer.setText(readMessage);
}

if(msg.what == CONNECTING_STATUS){
if(msg.arg1 == 1){}
// mBluetoothStatus.setText("Connected to Device: " + (String)(msg.obj));
else{}
// mBluetoothStatus.setText("Connection Failed");
}
}
};

if (mBTArrayAdapter == null) {
// Device does not support Bluetooth
// mBluetoothStatus.setText("Status: Bluetooth not found");
Toast.makeText(getApplicationContext(),"Bluetooth device not found!",Toast.LENGTH_SHORT).show();
}
else {
/* Up.setOnClickListener(new View.OnClickListener(){
@override
public void onClick(View v){
commandFromForward=1;
}
});
Down.setOnClickListener(new View.OnClickListener(){
@override
public void onClick(View v){
commandFromReverse=2;
}
});
Left.setOnClickListener(new View.OnClickListener(){
@override
public void onClick(View v){
commandFromLeft=4;
}
});
Right.setOnClickListener(new View.OnClickListener(){
@override
public void onClick(View v){
commandFromRight=8;
if(mConnectedThread != null) //First check to make sure thread created
mConnectedThread.write(Integer.toString(commandFromRight));
}
});*/

checkConnected();

new Thread()
{
public void run() {
boolean fail = false;

BluetoothDevice mdevice = mBTAdapter.getRemoteDevice(rBTaddress);

try {
mBTSocket = createBluetoothSocket(mdevice);
} catch (IOException e) {
fail = true;
Toast.makeText(getBaseContext(), "Socket creation failed", Toast.LENGTH_SHORT).show();
}
// Establish the Bluetooth socket connection.
try {
mBTSocket.connect();
} catch (IOException e) {
try {
fail = true;
mBTSocket.close();
mHandler.obtainMessage(CONNECTING_STATUS, -1, -1)
.sendToTarget();
} catch (IOException e2) {
//insert code to deal with this
Toast.makeText(getBaseContext(), "Socket creation failed", Toast.LENGTH_SHORT).show();
}
}
if(fail == false) {
mConnectedThread = new ConnectedThread(mBTSocket);
mConnectedThread.start();

mHandler.obtainMessage(CONNECTING_STATUS, 1, -1, rBTname)
.sendToTarget();
}
}
}.start();

Up.setOnTouchListener(new View.OnTouchListener() {
@override
public boolean onTouch(View v, MotionEvent event) {
if (event.getAction()==MotionEvent.ACTION_DOWN){
commandFromForward=1;
}
if (event.getAction()==MotionEvent.ACTION_UP){
commandFromForward=0;
}
return false;
}
});
Down.setOnTouchListener(new View.OnTouchListener() {
@override
public boolean onTouch(View v, MotionEvent event) {
if (event.getAction()==MotionEvent.ACTION_DOWN){
commandFromReverse=2;
}
if (event.getAction()==MotionEvent.ACTION_UP){
commandFromReverse=0;
}
return false;
}
});
Left.setOnTouchListener(new View.OnTouchListener() {
@override
public boolean onTouch(View v, MotionEvent event) {
if (event.getAction()==MotionEvent.ACTION_DOWN){
commandFromLeft=4;
}
if (event.getAction()==MotionEvent.ACTION_UP){
commandFromLeft=0;
}
return false;
}
});
Right.setOnTouchListener(new View.OnTouchListener() {
@override
public boolean onTouch(View v, MotionEvent event) {
if (event.getAction()==MotionEvent.ACTION_DOWN){
commandFromRight=8;
}
if (event.getAction()==MotionEvent.ACTION_UP){
commandFromRight=0;
}
return false;
}
});

if (mConnectedThread != null) {
mConnectedThread.write("stdc_init");
}
else if (mConnectedThread==null) {
toastMe("It seems your bluetooth module is disconnected. Please connect it and restart.","long");
}



/*
mScanBtn.setOnClickListener(new View.OnClickListener() {
@override
public void onClick(View v) {
bluetoothOn();
}
});

mOffBtn.setOnClickListener(new View.OnClickListener(){
@override
public void onClick(View v){
bluetoothOff(v);
}
});

mListPairedDevicesBtn.setOnClickListener(new View.OnClickListener() {
@override
public void onClick(View v){
listPairedDevices(v);
}
});

mDiscoverBtn.setOnClickListener(new View.OnClickListener(){
@override
public void onClick(View v){
discover(v);
}
});
*/
}
final Handler ha=new Handler();
ha.postDelayed(new Runnable() {

@override
public void run() {
if (mConnectedThread != null) {
sendCumulativeCommand(commandFromForward,commandFromReverse,commandFromLeft,commandFromRight);
}
ha.postDelayed(this, 100);
}
}, 100);

}

public void toastMe(String toastMessage, String type){
if (type=="long") {
Toast.makeText(getApplicationContext(), toastMessage, Toast.LENGTH_LONG).show();
}
else if (type=="short") {
Toast.makeText(getApplicationContext(), toastMessage, Toast.LENGTH_SHORT).show();
}
else {
Toast.makeText(getApplicationContext(), toastMessage, Toast.LENGTH_SHORT).show();
}
/* try {
synchronized (this) {
this.wait(1000);
}
}
catch (InterruptedException ie){
System.out.println("Interrupted");
}*/
}

public void sendCumulativeCommand(int fd, int bk, int rt, int lt){
int cumulativeCommand=fd+bk+rt+lt;
mConnectedThread.write(Integer.toString(cumulativeCommand));
}
@override
public boolean onCreateOptionsMenu (Menu menu){

getMenuInflater().inflate(R.menu.stdc_menu, menu);
return true;
}

public void checkConnected()
{
// true == headset connected && connected headset is support hands free
int state = BluetoothAdapter.getDefaultAdapter().getProfileConnectionState(BluetoothProfile.HEADSET);
if (state != BluetoothProfile.STATE_CONNECTED)
return;

try
{
BluetoothAdapter.getDefaultAdapter().getProfileProxy(getApplicationContext(), serviceListener, BluetoothProfile.HEADSET);
}
catch (Exception e)
{
e.printStackTrace();
}
}
private BluetoothProfile.ServiceListener serviceListener = new BluetoothProfile.ServiceListener()
{
@override
public void onServiceDisconnected(int profile)
{

}

@override
public void onServiceConnected(int profile, BluetoothProfile proxy)
{
for (BluetoothDevice device : proxy.getConnectedDevices())
{
rBTaddress=device.getAddress();
rBTname=device.getName();
Log.i("onServiceConnected", "|" + device.getName() + " | " + device.getAddress() + " | " + proxy.getConnectionState(device) + "(connected = "
+ BluetoothProfile.STATE_CONNECTED + ")");
}

BluetoothAdapter.getDefaultAdapter().closeProfileProxy(profile, proxy);
}
};

@override
public boolean onOptionsItemSelected (MenuItem item){
int id = item.getItemId();
switch (id) {
case R.id.howtouse_controller:
displayAboutStandardController();
}
return true;
}

public void displayAboutStandardController() {
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setTitle("About the standard controller");
builder.setMessage(R.string.about_stdc);
builder.setPositiveButton("OK", new DialogInterface.OnClickListener() {
@override
public void onClick(DialogInterface dialog, int which) {
dialog.dismiss();
}
});
builder.show();
}
private void bluetoothOn(){
if (!mBTAdapter.isEnabled()) {
Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
// mBluetoothStatus.setText("Bluetooth enabled");
Toast.makeText(getApplicationContext(),"Bluetooth turned on",Toast.LENGTH_SHORT).show();

}
else{
Toast.makeText(getApplicationContext(),"Bluetooth is already on", Toast.LENGTH_SHORT).show();
}
}

// Enter here after user selects "yes" or "no" to enabling radio
@override
protected void onActivityResult(int requestCode, int resultCode, Intent Data){
// Check which request we're responding to
if (requestCode == REQUEST_ENABLE_BT) {
// Make sure the request was successful
if (resultCode == RESULT_OK) {
// The user picked a contact.
// The Intent's data Uri identifies which contact was selected.
// mBluetoothStatus.setText("Enabled");
}
else{}
// mBluetoothStatus.setText("Disabled");
}
}

private void bluetoothOff(View view){
mBTAdapter.disable(); // turn off
// mBluetoothStatus.setText("Bluetooth disabled");
Toast.makeText(getApplicationContext(),"Bluetooth turned Off", Toast.LENGTH_SHORT).show();
}

private void discover(View view){
// Check if the device is already discovering
if(mBTAdapter.isDiscovering()){
mBTAdapter.cancelDiscovery();
Toast.makeText(getApplicationContext(),"Discovery stopped",Toast.LENGTH_SHORT).show();
}
else{
if(mBTAdapter.isEnabled()) {
mBTArrayAdapter.clear(); // clear items
mBTAdapter.startDiscovery();
Toast.makeText(getApplicationContext(), "Discovery started", Toast.LENGTH_SHORT).show();
registerReceiver(blReceiver, new IntentFilter(BluetoothDevice.ACTION_FOUND));
}
else{
Toast.makeText(getApplicationContext(), "Bluetooth not on", Toast.LENGTH_SHORT).show();
}
}
}

final BroadcastReceiver blReceiver = new BroadcastReceiver() {
@override
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if(BluetoothDevice.ACTION_FOUND.equals(action)){
BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
// add the name to the list
mBTArrayAdapter.add(device.getName() + "\n" + device.getAddress());
mBTArrayAdapter.notifyDataSetChanged();
}
}
};

private void listPairedDevices(View view){
mPairedDevices = mBTAdapter.getBondedDevices();
if(mBTAdapter.isEnabled()) {
// put it's one to the adapter
for (BluetoothDevice device : mPairedDevices)
mBTArrayAdapter.add(device.getName() + "\n" + device.getAddress());

Toast.makeText(getApplicationContext(), "Show Paired Devices", Toast.LENGTH_SHORT).show();
}
else
Toast.makeText(getApplicationContext(), "Bluetooth not on", Toast.LENGTH_SHORT).show();
}

private AdapterView.OnItemClickListener mDeviceClickListener = new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> av, View v, int arg2, long arg3) {

if(!mBTAdapter.isEnabled()) {
Toast.makeText(getBaseContext(), "Bluetooth not on", Toast.LENGTH_SHORT).show();
return;
}

// mBluetoothStatus.setText("Connecting...");
// Get the device MAC address, which is the last 17 chars in the View
String info = ((TextView) v).getText().toString();
final String address = info.substring(info.length() - 17);
final String name = info.substring(0,info.length() - 17);

// Spawn a new thread to avoid blocking the GUI one
new Thread()
{
public void run() {
boolean fail = false;

BluetoothDevice mdevice = mBTAdapter.getRemoteDevice(address);

try {
mBTSocket = createBluetoothSocket(mdevice);
} catch (IOException e) {
fail = true;
Toast.makeText(getBaseContext(), "Socket creation failed", Toast.LENGTH_SHORT).show();
}
// Establish the Bluetooth socket connection.
try {
mBTSocket.connect();
} catch (IOException e) {
try {
fail = true;
mBTSocket.close();
mHandler.obtainMessage(CONNECTING_STATUS, -1, -1)
.sendToTarget();
} catch (IOException e2) {
//insert code to deal with this
Toast.makeText(getBaseContext(), "Socket creation failed", Toast.LENGTH_SHORT).show();
}
}
if(fail == false) {
mConnectedThread = new ConnectedThread(mBTSocket);
mConnectedThread.start();

mHandler.obtainMessage(CONNECTING_STATUS, 1, -1, name)
.sendToTarget();
}
}
}.start();
}
};


private BluetoothSocket createBluetoothSocket(BluetoothDevice device) throws IOException {
try {
final Method m = device.getClass().getMethod("createInsecureRfcommSocketToServiceRecord", UUID.class);
return (BluetoothSocket) m.invoke(device, BTMODULEUUID);
} catch (Exception e) {
Log.e(TAG, "Could not create Insecure RFComm Connection",e);
}
return device.createRfcommSocketToServiceRecord(BTMODULEUUID);
}

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;

// Get the input and output streams, using temp objects because
// member streams are final
try {
tmpIn = socket.getInputStream();
tmpOut = socket.getOutputStream();
} catch (IOException e) { }

mmInStream = tmpIn;
mmOutStream = tmpOut;
}

public void run() {
byte[] buffer = new byte[1024]; // buffer store for the stream
int bytes; // bytes returned from read()
// Keep listening to the InputStream until an exception occurs
while (true) {
try {
// Read from the InputStream
bytes = mmInStream.available();
if(bytes != 0) {
buffer = new byte[1024];
SystemClock.sleep(100); //pause and wait for rest of data. Adjust this depending on your sending speed.
bytes = mmInStream.available(); // how many bytes are ready to be read?
bytes = mmInStream.read(buffer, 0, bytes); // record how many bytes we actually read
mHandler.obtainMessage(MESSAGE_READ, bytes, -1, buffer)
.sendToTarget(); // Send the obtained bytes to the UI activity
}
} catch (IOException e) {
e.printStackTrace();

break;
}
}
}

/* Call this from the main activity to send data to the remote device */
public void write(String input) {
byte[] bytes = input.getBytes(); //converts entered String into bytes
try {
mmOutStream.write(bytes);
} catch (IOException e) { }
}

/* Call this from the main activity to shutdown the connection */
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) { }
}
}










}

However, what the sample does is let the user select a device, and then establish a ConnectedThread with it.

What I want to do is to have a connected device beforehand (the device will have already been connected), and just assume that this connected device is the desired one, and establish a ConnectedThread with it. For this, I think we'll need the specific address of the device it is connected to. How can that be done?

 

[KBU2]

What device are you using to pair the Bluetooth with?

1. Under Control Panel, open the Devices and Printers section.
2. Right-click on the HC-05 or HC-06 Bluetoothdevice, and select Properties.
3. Click the Hardware menu, and then click Properties.
4. Click the Details menu, and then select the Property as Bluetooth Device Address

 

[shlokj]

What device are you using to pair the Bluetooth with?

1. Under Control Panel, open the Devices and Printers section.
2. Right-click on the HC-05 or HC-06 Bluetoothdevice, and select Properties.
3. Click the Hardware menu, and then click Properties.
4. Click the Details menu, and then select the Property as Bluetooth Device Address

I can't do that, since my app will be used with different devices. The address can be anything, since I'm distributing this app to others.

 

[KBU2]

I can't do that, since my app will be used with different devices. The address can be anything, since I'm distributing this app to others.

This question is going to be difficult to answer because one needs to know what type of device that you're going to use because there's different methods on how one can retrieve that information thats requested. Fortunately these formalities are put in place to locate a device if it's used for hacking purposes.

 

[shlokj]

This question is going to be difficult to answer because one needs to know what type of device that you're going to use because there's different methods on how one can retrieve that information thats requested. Fortunately these formalities are put in place to locate a device if it's used for hacking purposes.

In the java code, we can query the already known paired devices. I wanted to know how I can explicitly find out the CONNECTED one.

 

[Deleted User]

Looks like you can do it using the BluetoothManager, which provides a getConnectedDevices() method

https://developer.android.com/reference/android/bluetooth/BluetoothManager

 

[KBU2]

Just out of curiosity what's your implementing there, can't that be used in hacking into a device Bluetooth address? YES or No?

 

[Unforgiven]

Development thread moved to the dev area for better exposure.

 

[Deleted User]

Just out of curiosity what's your implementing there, can't that be used in hacking into a device Bluetooth address? YES or No?

The pairing process for a bluetooth device involves entering a PIN. To obtain this, the user must have physical access to the target device. So I don't think surreptitiously gaining access to a device is an issue.
Besides, it's not really our place to quiz someone on their intended use of a published interface.

 

[shlokj]

Just out of curiosity what's your implementing there, can't that be used in hacking into a device Bluetooth address? YES or No?

No, not exactly. Whatever my code does is just after connection, and since you're already connected, you aren't exactly hacking.

 

[shlokj]

I tried it out, get this error (screenshot attached below):
https://drive.google.com/open?id=0B8a5LMaQdTMtSnY4MjktZ0VsQlZURlRXX01wS3NsdVpJYWE0

This is my code:

//package here

import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothGatt;
import android.bluetooth.BluetoothManager;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.widget.TextView;

import java.util.List;

public class TerminalActivity extends AppCompatActivity {
@override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_terminal);
TextView connectedDevices=(TextView) findViewById(R.id.connected_devices);
BluetoothManager manager = (BluetoothManager) getSystemService(BLUETOOTH_SERVICE);
List<BluetoothDevice> connected = manager.getConnectedDevices(BluetoothGatt.GATT);
// if (connected.size()>=1) {
Log.i("Connected Devices: ", connected.get(0).toString() + "");
connectedDevices.setText(connected.get(0).toString());
// }
}

}

Tell me if I should attach an APK for testing.

 

[shlokj]

Development thread moved to the dev area for better exposure.

Thank you. By the way, how do we get code-style formatting (since my code doesn't look neat as normal text), and image insertion without the URL (image from PC)?

 

[Unforgiven]

Thank you. By the way, how do we get code-style formatting (since my code doesn't look neat as normal text), and image insertion without the URL (image from PC)?

Put [code][/code] tags around your code.
Example:
[code]
line 1...
line 2...
line 3...
.
.
.
...etc
[/code]
Produces:

line 1...
line 2...
line 3...
.
.
.
...etc

 

[Deleted User]

This line

List<BluetoothDevice> connected = manager.getConnectedDevices(BluetoothGatt.GATT);

returned an empty list.

 

[shlokj]

This line

List<BluetoothDevice> connected = manager.getConnectedDevices(BluetoothGatt.GATT);

returned an empty list.

Exactly. Why do I get this even though there is a live connection?

 

[shlokj]

It would be GREAT if someone could test this app out. I've attached the APK.

In the main activity, (the one in my app with three buttons) click on the "Start Terminal" button. Make sure your bluetooth device is connected before you do so. Please tell me what happens.

I would appreciate it if someone could help me out with this.