How to connect more than one Bluetooth audio devices with android phones, one device should record and other should play?

Question

I am trying to develop one audio record play application with Bluetooth devices I need to satisfy below scenario.

• If there are more than one audio Bluetooth device is connected, if one of the device is recording audio other device should play the audio simultaneously.

I can connect the Bluetooth devices in my MainActivity class below but the audio is not playing with the Bluetooth devices.

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.Random;
import java.util.Set;
import java.util.TimeZone;
import java.util.UUID;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
import android.app.ProgressDialog;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.res.Configuration;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.ColorMatrix;
import android.graphics.ColorMatrixColorFilter;
import android.graphics.PorterDuff.Mode;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
import android.os.Environment;
import android.os.Handler;
import android.os.Message;
import android.preference.PreferenceManager;
import android.provider.Settings;
import android.util.Log;
import android.view.KeyEvent;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.view.Window;
import android.view.WindowManager;
import android.view.inputmethod.InputMethodManager;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;

public class Main extends Activity implements Runnable 
{
    protected static final String TAG = "TAG";
    private static final int REQUEST_CONNECT_DEVICE = 1;
    private static final int REQUEST_ENABLE_BT = 2;
    Button mScan;
    BluetoothAdapter mBluetoothAdapter;
    private UUID applicationUUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
    private ProgressDialog mBluetoothConnectProgressDialog;
    private BluetoothSocket mBluetoothSocket;
    BluetoothDevice mBluetoothDevice;

    @Override
    public void onCreate(Bundle mSavedInstanceState) 
    {
        super.onCreate(mSavedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
            WindowManager.LayoutParams.FLAG_FULLSCREEN);
        setContentView(R.layout.main);
        mScan = (Button) findViewById(R.id.Scan);
        mScan.setOnClickListener(new View.OnClickListener() 
        {
            public void onClick(View mView) 
            {
                mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
                if (mBluetoothAdapter == null) 
                {
                    Toast.makeText(Main.this, "Message1", 2000).show();
                } 
                else 
                {
                    if (!mBluetoothAdapter.isEnabled()) 
                    {
                        Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
                        startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
                    } 
                    else 
                    {
                        ListPairedDevices();
                        Intent connectIntent = new Intent(Main.this, DeviceListActivity.class);
                        startActivityForResult(connectIntent, REQUEST_CONNECT_DEVICE);
                    }
                }
            }
        });

        mTune.setOnClickListener(new View.OnClickListener() 
        {
            public void onClick(View mView) 
            {
                mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
                if (mBluetoothAdapter == null) 
                {
                    Toast.makeText(Main.this, "Message2", 2000).show();
                } 
                else 
                {
                    if (!mBluetoothAdapter.isEnabled()) 
                    {
                        Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
                        startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
                    } 
                    else 
                    {
                        ListPairedDevices();
                        Intent connectIntent = new Intent(Main.this, DeviceListActivity.class);
                        startActivityForResult(connectIntent, REQUEST_CONNECT_DEVICE);
                    }
                }
            }
        });
    }// onCreate

    public void onActivityResult(int mRequestCode, int mResultCode, Intent mDataIntent) 
    {
        super.onActivityResult(mRequestCode, mResultCode, mDataIntent);

        switch (mRequestCode) 
        {
            case REQUEST_CONNECT_DEVICE:
                if (mResultCode == Activity.RESULT_OK) 
                {
                    Bundle mExtra = mDataIntent.getExtras();
                    String mDeviceAddress = mExtra.getString("DeviceAddress");
                    Log.v(TAG, "Coming incoming address " + mDeviceAddress);
                    mBluetoothDevice = mBluetoothAdapter.getRemoteDevice(mDeviceAddress);
                    mBluetoothConnectProgressDialog = ProgressDialog.show(this, "Connecting...", mBluetoothDevice.getName() + " : " + mBluetoothDevice.getAddress(), true, false);
                    Thread mBlutoothConnectThread = new Thread(this);
                    mBlutoothConnectThread.start();
                    //pairToDevice(mBluetoothDevice); This method is replaced by progress dialog with thread
                }
                break;

            case REQUEST_ENABLE_BT:
                if (mResultCode == Activity.RESULT_OK) 
                {
                    ListPairedDevices();
                    Intent connectIntent = new Intent(Main.this, DeviceListActivity.class);
                    startActivityForResult(connectIntent, REQUEST_CONNECT_DEVICE);
                } 
                else 
                {
                    Toast.makeText(Main.this, "Message", 2000).show();
                }
                break;
        }
    }

    private void ListPairedDevices() 
    {
        Set<BluetoothDevice> mPairedDevices = mBluetoothAdapter.getBondedDevices();
        if (mPairedDevices.size() > 0) 
        {
            for (BluetoothDevice mDevice : mPairedDevices) 
            {
                Log.v(TAG, "PairedDevices: " + mDevice.getName() + " " + mDevice.getAddress());
            }
        }
    }

    public void run() 
    {
        try 
        {
            mBluetoothSocket = mBluetoothDevice.createRfcommSocketToServiceRecord(applicationUUID);
            mBluetoothAdapter.cancelDiscovery();
            mBluetoothSocket.connect();
            mHandler.sendEmptyMessage(0);
        }
        catch (IOException eConnectException) 
        {
            Log.d(TAG, "CouldNotConnectToSocket", eConnectException);
             closeSocket(mBluetoothSocket);
             return;
        }
    }

    private void closeSocket(BluetoothSocket nOpenSocket) 
    {
        try 
        {
            nOpenSocket.close();
            Log.d(TAG, "SocketClosed");
        } 
        catch (IOException ex) 
        {
            Log.d(TAG, "CouldNotCloseSocket");
        }
    }

    private Handler mHandler = new Handler() 
    {
        @Override
        public void handleMessage(Message msg) 
        {
            mBluetoothConnectProgressDialog.dismiss();
            Toast.makeText(Main.this, "DeviceConnected", 5000).show();
        }
    };
} 

Answer 1

Based on all the research I have done, the answer is no. Unless you have multiple bluetooth chips in your phone/tablet/mp3 player (an extremeley unlikely scenario) or some kind of hub/reciever that is otherwise connected to the speaker set up in the house, you will be limited to one bluetooth speaker. However, it is possible to create more convoluted setups than a simple bluetooth connection. There are Bluetooth audio recievers that can plug in to a speaker's audio in cable. These combined with long wires and splitters copuld do your job. If you want to make it wireless, fm transmitters are a thing. The bluetooth reciever would connect to an fm transmitter and each speaker could be paired with an fm reciever and you're good to go.

If you do find a solution though, I would be very interested.