Develop Reference

Android: Disconnect bluetooth headset to connect my SPP app using bluetooth

I have a SPP Bluetooth app, the problem is this case.
The android device is connected to a Bluetooth Speaker, when i try to connect to my SPP Micro device i can't for the same reason the Bluetooth is already connected.
How i can disconnect the Bluetooth Speaker from my App so i can connect to my SPP micro device after the disconnection.
Thanks!
UPDATE:
Sorry, i forget to specify, the connection to the Bluetooth speaker is made before opening my app, its already connected to the speaker when i open my app and i want to disconnect the bluetooth speaker from my app that didn't connect to the bluetooth speaker and with my app close that connection

You need to manually disconnect your device by closing the socket
You need to check, If the devices are connected. If yes, call reset function
if (BluetoothDevice.ACTION_ACL_CONNECTED.equals(action)) {
resetConnection
}
ResetConnection function definition.
private void resetConnection() {
if (mBTInputStream != null) {
try {mBTInputStream.close();} catch (Exception e) {}
mBTInputStream = null;
}
if (mBTOutputStream != null) {
try {mBTOutputStream.close();} catch (Exception e) {}
mBTOutputStream = null;
}
if (mBTSocket != null) {
try {mBTSocket.close();} catch (Exception e) {}
mBTSocket = null;
}
}
Edit 1
You will have to create a new BluetoothSocket and then call this method getRemoteDevice().
getRemoteDevice ()
Added in API level 5
Get the remote device this socket is connecting or connected to.
Here is a link to Documentation BluetoothSocket

Android bluetooth connection with bluetooth rs232 adapter

I've been planning to make an Android App, that would communicate with this bluetooth rs232 adapter
http://www.nordfield.com/wireless-serial-rs232-bluetooth-adapter
and I'm not sure what should I do with UUID in this case? Will I be able to start a connection with an application, that would look like BluetoothChat sample app from Google?
https://android.googlesource.com/platform/development/+/25b6aed7b2e01ce7bdc0dfa1a79eaf009ad178fe/samples/BluetoothChat/

Well, I've solved the problem already. Actually there is possibility to create Bluetooth connection without knowing device's UUID. It is achieved by this code:
public ConnectThread(BluetoothDevice device) {
mmDevice = device;
BluetoothSocket tmp = null;
try {
Method method;
method = device.getClass().getMethod("createRfcommSocket", new Class[] { int.class } );
tmp = (BluetoothSocket) method.invoke(device, 1);
} catch (Exception e) { }
mmSocket = tmp;
}
All of the rest of connection management is done the same as in BluetoothChat sample app from Google.

Android Bluetooth Can't Connect using createRfcommSocketServiceRecord

I already managed to get it working using this method at android 2.3.3 version, but now I am testing using another device with 2.2 version..
And I can find many devices using discovery, but can't connect to other devices using:
BluetoothSocket socket = deviceToConnect.createRfcommSocketToServiceRecord(UUID.fromString(MY_UUID));
On the other side, I am using the proper thread to accept the connection using :
mBluetoothAdapter.cancelDiscovery();
BluetoothServerSocket ss;
try {
ss = mBluetoothAdapter.listenUsingRfcommWithServiceRecord(MainPage.SD_FolderName, UUID.fromString(MY_UUID));
new Thread(new ListenerHandler(ss, this, resultCode)).start();
} catch (IOException e) {
Toast.makeText(this, "There was a problem opening the bluetooth server socket!", Toast.LENGTH_LONG).show();
finish();
}
Then on the ListenerHandler I have this:
BluetoothSocket clientSocket = ss.accept();
But the connection is never stablished, any thoughs?
Thanks in advance!

How to send AT commands based on BT Hands-Free profile in android?

I am trying to establish Bluetooth connection between an Android device with other mobile phone over Handsfree profile. I am using following code -
private static final UUID MY_UUID = UUID.fromString("0000111F-0000-1000-8000-00805F9B34FB"); // UUID for Hands free profile
// Some code...
// Get Bluetooth Adapter.
m_oBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
// Some code...
// For paired BT device, getting a connection established.
if(null != m_oBluetoothDevice)
{
if(BluetoothDevice.BOND_BONDED == m_oBluetoothDevice.getBondState())
{
try
{
m_oBluetoothSocket = m_oBluetoothDevice.createRfcommSocketToServiceRecord(MY_UUID);
m_oBluetoothSocket.connect();
Log.i(TAG, "Socket Connected");
}
catch(Exception e)
{
if(null != m_oBluetoothSocket)
{
Log.i(TAG, "Closing socket");
try
{
m_oBluetoothSocket.close();
}
catch (Exception e1)
{
Log.i(TAG, "Error while closing socket : " + e1.getMessage());
}
}
}
}
}
I can create RFCOMMSocket using this code.
Now I want to send AT commands based on Bluetooth Hands-Free profile. e.g. If other mobile phone receives a phone call, my Android device can reject this call by sending AT command- "+CHUP". I am not sure whether this is possible or not.
At this point, I am stuck. I have read Bluetooth APIs where I found -
BluetoothHeadset.ACTION_VENDOR_SPECIFIC_HEADSET_EVENT
Can we use this Intent for sending AT commands? Is this a proper way to send AT command based on Bluetooth Hands-Free profile? Please someone help me out and give me proper direction.
Any input from you all will be great help for me.
Thanks in advance.

You need to create InputStream and OutputStream so you can talk to the phone:
mmInStream = m_oBluetoothSocket.getInputStream();
mmOutStream = m_oBluetoothSocket.getOutputStream();
To setup the HFP connection you start to send:
mmOutStream.write("AT+BRSF=20\r".getBytes());
Where 20 is code for what you support of HFP.
And to read from the phone:
buffer = new byte[200];
mmInStream.read(buffer);
command = new String(buffer).trim();
So now you can talk beetwen the devices and you can read more about the Handsfree profile on https://www.bluetooth.org/docman/handlers/downloaddoc.ashx?doc_id=238193

Adding reference to AT commnads
http://forum.xda-developers.com/showthread.php?t=1471241
http://www.zeeman.de/wp-content/uploads/2007/09/ubinetics-at-command-set.pdf

Connecting with embedded device over bluetooth? [duplicate]

I'm currently working on an Android application that connects to an instrument via Bluetooth and need to write string commands and receive string responses back. Currently I have the connect/read/write working for TCP/IP over Wi-Fi and now trying to implement Bluetooth. But I am running into some roadblocks. I have been searching the web trying to find examples of something similar and haven't had any luck. I have been using the Android developer resource example: Bluetooth Chat as my main reference point.
My current code seems to work.. Then it throws a Service Discovery Failed exception at the point of the connection. I am using the DeviceListActivity class to do the discovery and selecting of the device I want to connect to. It returns anActivityResult and then my Bluetooth class waits for it to handle that and then does the connect to it. The code beneath is almost identical to the Bluetooth Chat App.
public void onActivityResult(int requestCode, int resultCode, Intent data) {
if(!m_BluetoothAdapter.isEnabled())
{
m_BluetoothAdapter.enable();
}
switch (requestCode) {
case REQUEST_CONNECT_DEVICE:
// When DeviceListActivity returns with a device to connect
if (resultCode == Activity.RESULT_OK) {
// Get the device MAC address
String address = data.getExtras()
.getString(DeviceListActivity.EXTRA_DEVICE_ADDRESS);
// Get the BLuetoothDevice object
BluetoothDevice device = m_BluetoothAdapter.getRemoteDevice(address);
// Attempt to connect to the device
connect(device);
}
break;
case REQUEST_ENABLE_BT:
// When the request to enable Bluetooth returns
if (resultCode == Activity.RESULT_OK) {
// Bluetooth is now enabled, so set up a chat session
}
else {
// User did not enable Bluetooth or an error occured
Toast.makeText(this, "Bluetooth not enabled", Toast.LENGTH_SHORT).show();
finish();
}
}
}
This is my connect function:
private static final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
private void connect(BluetoothDevice device) {
m_Device = device;
BluetoothSocket tmp = null;
// Get a BluetoothSocket for a connection with the
// given BluetoothDevice
try {
tmp = device.createRfcommSocketToServiceRecord(MY_UUID);
}
catch (IOException e) {
}
m_Socket = tmp;
m_BluetoothAdapter.cancelDiscovery();
try {
// This is a blocking call and will only return on a
// successful connection or an exception
m_Socket.connect();
}
catch (IOException e) {
try {
m_Socket.close();
}
catch (IOException e2) {
}
return;
}
}
Hopefully, whatever I am doing wrong is simple, but I'm afraid it's never that easy. This is my first time doing any Bluetooth development, and maybe I'm doing something blatantly wrong... But I'm not sure why I get the service discovery failed exception.
You can pair/find the device at all times manually on the phone... It does require a passcode, but I don't think that is the problem that I am having.

After three days I got it figured out thanks to some very helpful posts.
I had to replace:
tmp = device.createRfcommSocketToServiceRecord(MY_UUID);
with:
Method m = device.getClass().getMethod("createRfcommSocket", new Class[] {int.class});
tmp = (BluetoothSocket) m.invoke(device, 1);
and voilà it works!

As of API 15 you can use the following method:
Try replacing your UUID with the return value of getUuids() method of BluetoothDevice class.
What worked for me was something like this:
UUID uuid = bluetoothDevice.getUuids()[0].getUuid();
BluetoothSocket socket = bluetoothDevice.createRfcommSocketToServiceRecord(uuid);
The reason this works is that different devices support different UUIDs and by getting the UUIDs of the device using getUuids you are supporting all features and devices.
Another interesting new method (supported since API 14) is this: BluetoothHealth.getConnectionState. Haven't tried it but looks promising...

This was a suggested edit from an anonymous user attempting to reply to the accepted answer.
One big difference between your before and after code is the UUID you are passing. I found my answer here: http://developer.android.com/reference/android/bluetooth/BluetoothDevice.html#createRfcommSocketToServiceRecord(java.util.UUID)
I had to replace:
tmp = device.createRfcommSocketToServiceRecord(MY_UUID);
with:
private static final UUID SPP_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
tmp = device.createRfcommSocketToServiceRecord(SPP_UUID);
and voila it works!
The original code is for a peer to peer android app. It makes no sense to use the app UUID when connecting to a simple serial bluetooth device. Thats why discovery fails.

So as it mentioned above, the point is that you need to use the UUID that the server is waiting for.
If you are connecting to a bluetooth device, such as a headset or mouse, you need to check which UUIDs the device is listening for. You can see the UUIDs like this.
UUID[] uuids = bluetoothDevice.getUuids();
And if you want to know what these UUIDs mean, see this.

This is a realy old one question but i found that using the createInsecureRfcommSocketToServiceRecord() instead of createRfcommSocketToServiceRecord() along with the getUuids() previously mentioned do the trick for me
UUID uuid = bluetoothDevice.getUuids()[0].getUuid();
BluetoothSocket socket = bluetoothDevice.createInsecureRfcommSocketToServiceRecord(uuid);