connecting paired devices in Bluetooth using android studio

connecting paired devices in Bluetooth using android studio - android

I have created an app to display paired devices successfully but not able to connect to it.
I tried a lot but i'm getting "app has been stopped working".
Please advise on issues in my code to connect to paired devices:
public class MainActivity extends AppCompatActivity {
public static final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
BluetoothAdapter bt;
ArrayAdapter<String> listAdapter;
Set<BluetoothDevice> devicesArray;
ListView listview;
Button connectbutton;
Handler mHandler = new Handler(){
#Override
public void handleMessage(Message msg) {
// TODO Auto-generated method stub
super.handleMessage(msg);
Toast.makeText(getApplicationContext(), "CONNECT", Toast.LENGTH_SHORT).show();
}
};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
init();
if(bt==null){
Toast.makeText(getApplicationContext(), "no bluetooth on device",Toast.LENGTH_SHORT).show();
finish();
}
else
{
if(!bt.isEnabled()){
Intent intent=new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(intent,1);
}
}
listview.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View arg1, int arg2, long arg3) {
Toast.makeText(getApplicationContext(), (CharSequence) parent.getItemAtPosition(arg2), Toast.LENGTH_SHORT).show();
if(bt.isDiscovering())
{
bt.cancelDiscovery();
}
BluetoothDevice selectedDevice = (BluetoothDevice) parent.getItemAtPosition(arg2);
}
});
}
public void onButtonClick(View v)
{
getpaireddevices();
}
public void onButtonClick2(View v)
{
startdiscovery();
}
private void getpaireddevices() {
devicesArray = bt.getBondedDevices();
if (devicesArray.size() > 0) {
for (BluetoothDevice device : devicesArray)
listAdapter.add(device.getName());
}
}
private void startdiscovery()
{
bt.cancelDiscovery();
bt.startDiscovery();
}
private void init() {
listview = (ListView)findViewById(R.id.listView);
connectbutton = (Button)findViewById(R.id.button);
listAdapter = new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1,0);
listview.setAdapter(listAdapter);
bt= BluetoothAdapter.getDefaultAdapter();
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if(resultCode == RESULT_CANCELED)
{
Toast.makeText(getApplicationContext(), "bluetooth must be turned on to continue",Toast.LENGTH_SHORT).show();
finish();
}
}

when I wanted to get a list of connected Bluetooth devices for my app aw well and this helped me,
Get List Of Paired Bluetooth Devices
in the first link, besides giving you a list of paired devices it has onclick, which then I used second link (how to send images via Bluetooth) to communicate with my selected device
Sending Images Over Bluetooth In Android
example:
class SendData extends Thread {
private BluetoothDevice device = null;
private BluetoothSocket btSocket = null;
private OutputStream outStream = null;
public SendData(){
device = mBluetoothAdapter.getRemoteDevice(address);
try
{
btSocket = device.createRfcommSocketToServiceRecord(MY_UUID);
}
catch (Exception e) {
// TODO: handle exception
}
mBluetoothAdapter.cancelDiscovery();
try {
btSocket.connect();
} catch (IOException e) {
try {
btSocket.close();
} catch (IOException e2) {
}
}
Toast.makeText(getBaseContext(), "Connected to " + device.getName(), Toast.LENGTH_SHORT).show();
try {
outStream = btSocket.getOutputStream();
} catch (IOException e) {
}
}
public void sendMessage()
{
try {
mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
Bitmap bm = BitmapFactory.decodeResource(getResources(), R.drawable.white);
ByteArrayOutputStream baos = new ByteArrayOutputStream();
bm.compress(Bitmap.CompressFormat.JPEG, 100,baos); //bm is the bitmap object
byte[] b = baos.toByteArray();
Toast.makeText(getBaseContext(), String.valueOf(b.length), Toast.LENGTH_SHORT).show();
outStream.write(b);
outStream.flush();
} catch (IOException e) {
}
}
}
}
hope it helps you too!

Related

Android Studio Bluetooth ListView

I wanted to make bluetooth applications for arduino so that I could connect to the HC-05 module. And I found a tutorial on how to make a bluetooth connection (http://mcuhq.com/27/simple-android-bluetooth-application-with-arduino-example) When I downloaded the code from github, the application starts and everything works and connects. But the problem is that I can't open a new activity because the project is probably for 15 API and the new activity needs at least 16 so I decided to make such an application on my own based on the code from this website. And here I have a problem because when I make my phone search for bluetooth devices, nothing is displayed on my ListView.
This is my code `
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
offon = findViewById(R.id.BtBtn);
TV = findViewById(R.id.BtTv);
TV2 = findViewById(R.id.textView2);
TV3 = findViewById(R.id.bluetooth_status);
Next = findViewById(R.id.button2);
LV = findViewById(R.id.ListView);
disc = findViewById(R.id.button3);
ArrayAdapter = new ArrayAdapter<>(this, android.R.layout.simple_list_item_1);
adapter = BluetoothAdapter.getDefaultAdapter();
LV.setAdapter(ArrayAdapter);
LV.setOnItemClickListener(DeviceList);
handler = new Handler(Looper.getMainLooper()){
#Override
public void handleMessage(Message msg){
if(msg.what == MESSAGE_READ){
String readMessage = null;
readMessage = new String((byte[]) msg.obj, StandardCharsets.UTF_8);
TV2.setText(readMessage);
}
if(msg.what == CONNECTING_STATUS){
char[] sConnected;
if(msg.arg1 == 1)
TV3.setText(getString(R.string.BTConnected) + msg.obj);
else
TV3.setText(getString(R.string.BTconnFail));
}
}
};
if (adapter.isEnabled()){
TV.setText("Bluetooth ON");
}else TV.setText("Bluetooth OFF");
disc.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
discovery();
if (!adapter.isEnabled()){
Toast.makeText(getBaseContext(), getString(R.string.BTnotOn), Toast.LENGTH_SHORT).show();
}
}
});
offon.setOnClickListener(new View.OnClickListener() {
#SuppressLint("MissingPermission")
#Override
public void onClick(View view) {
if (adapter.isEnabled()) {
adapter.disable();
TV.setText("Bluetooth OFF");
}else {
adapter.enable();
TV.setText("Bluetooth ON");
}
}
});
Next.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
open2activity();
}
});
}
public void open2activity(){
Intent intent = new Intent(this, MainActivity2.class);
startActivity(intent);
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent Data) {
super.onActivityResult(requestCode, resultCode, Data);
}
#SuppressLint("MissingPermission")
private void discovery(){
if (adapter.isDiscovering()){
adapter.cancelDiscovery();
Toast.makeText(getApplicationContext(), getString(R.string.DisStop), Toast.LENGTH_SHORT).show();
}
else{
if (adapter.isEnabled()){
ArrayAdapter.clear();
adapter.startDiscovery();
Toast.makeText(getApplicationContext(), getString(R.string.DisStart), Toast.LENGTH_SHORT).show();
registerReceiver(blReceiver, new IntentFilter(BluetoothDevice.ACTION_FOUND));
}
}
}
final BroadcastReceiver blReceiver = new BroadcastReceiver() {
#SuppressLint("MissingPermission")
#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);
ArrayAdapter.add(device.getName() + "\n" + device.getAddress());
ArrayAdapter.notifyDataSetChanged();
}
}
};
private AdapterView.OnItemClickListener DeviceList = new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
TV3.setText(getString(R.string.cConnet));
String info = ((TextView)view).getText().toString();
final String address = info.substring(info.length() - 17);
final String name = info.substring(0,info.length() - 17);
new Thread()
{
#SuppressLint("MissingPermission")
#Override
public void run() {
boolean fail = false;
BluetoothDevice device = adapter.getRemoteDevice(address);
try {
BTSocket = createBluetoothSocket(device);
} catch (IOException e) {
fail = true;
Toast.makeText(getBaseContext(), getString(R.string.ErrSockCrea), Toast.LENGTH_SHORT).show();
}
try {
BTSocket.connect();
} catch (IOException e) {
try {
fail = true;
BTSocket.close();
handler.obtainMessage(CONNECTING_STATUS, -1, -1)
.sendToTarget();
} catch (IOException e2) {
Toast.makeText(getBaseContext(), getString(ErrSockCrea), Toast.LENGTH_SHORT).show();
}
}
if(!fail) {
ConnectedThread = new ConnectedThread(BTSocket, handler);
ConnectedThread.start();
handler.obtainMessage(CONNECTING_STATUS, 1, -1, name)
.sendToTarget();
}
}
}.start();
}
};
#SuppressLint("MissingPermission")
private BluetoothSocket createBluetoothSocket(BluetoothDevice device) throws IOException {
try {
final Method m = device.getClass().getMethod("createInsecureRfcommSocketToServiceRecord", UUID.class);
return (BluetoothSocket) m.invoke(device, BT_MODULE_UUID);
} catch (Exception e) {
Log.e(TAG, "Could not create Insecure RFComm Connection",e);
}
return device.createRfcommSocketToServiceRecord(BT_MODULE_UUID);
}
}
`
I tried to do as above but nothing is displayed

How do I send Bluetooth data from another activity outside of Bluetooth class

I am having trouble with passing the data (send data) over the bluetooth socket from another Activity outside the Bluetooth Activity. I have multiple classes that I need to execute, a command to send a string through Bluetooth.
Everything works fine from within the Bluetooth class.
Here is my Bluetooth Class
public class BTadapter extends Activity implements OnItemClickListener {
ArrayAdapter<String> listAdapter;
ListView btlistView;
BluetoothAdapter btAdapter;
Set<BluetoothDevice> devicesArray;
ArrayList<String> pairedDevices;
ArrayList<BluetoothDevice> devices;
public static final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
protected static final int SUCCESS_CONNECT = 0;
protected static final int MESSAGE_READ = 1;
IntentFilter filter;
BroadcastReceiver receiver;
String tag = "debugging";
Handler mHandler = new Handler(){
#Override
public void handleMessage(Message msg) {
Log.i(tag, "in handler");
super.handleMessage(msg);
switch(msg.what){
case SUCCESS_CONNECT:
// DO something
ConnectedThread connectedThread = new ConnectedThread((BluetoothSocket)msg.obj);
Toast.makeText(getApplicationContext(), "CONNECTED TO ELD", Toast.LENGTH_LONG).show();
String s = "8";
connectedThread.write(s.getBytes());
s = System.getProperty("line.separator");
connectedThread.write(s.getBytes());
Log.i(tag, "Good Connection");
ConnectedThread btThread = new ConnectedThread((BluetoothSocket)msg.obj);connectedThread.start();
finish();
break;
case MESSAGE_READ:
Log.i(tag, "Message Receive POP");
byte[] readBuf = (byte[])msg.obj;
String string = new String(readBuf);
Toast.makeText(getApplicationContext(), string, Toast.LENGTH_LONG).show();
break;
}
}
};
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.btadapter);
init();
if(btAdapter==null){
Toast.makeText(getApplicationContext(), "No bluetooth detected", Toast.LENGTH_LONG).show();
finish();
}
else{
if(!btAdapter.isEnabled()){
turnOnBT();
}
getPairedDevices();
startDiscovery();
}
}
private void startDiscovery() {
// TODO Auto-generated method stub
btAdapter.cancelDiscovery();
btAdapter.startDiscovery();
}
private void turnOnBT() {
// TODO Auto-generated method stub
Intent intent =new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(intent, 1);
}
private void getPairedDevices() {
// TODO Auto-generated method stub
devicesArray = btAdapter.getBondedDevices();
if(devicesArray.size()>0){
for(BluetoothDevice device:devicesArray){
pairedDevices.add(device.getName());
}
}
}
private void init() {
// TODO Auto-generated method stub
btlistView=(ListView)findViewById(R.id.btlistView);
btlistView.setOnItemClickListener(this);
listAdapter= new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1,0);
btlistView.setAdapter(listAdapter);
btAdapter = BluetoothAdapter.getDefaultAdapter();
pairedDevices = new ArrayList<String>();
filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);
devices = new ArrayList<BluetoothDevice>();
receiver = new BroadcastReceiver(){
#Override
public void onReceive(Context context, Intent intent) {
// TODO Auto-generated method stub
String action = intent.getAction();
if(BluetoothDevice.ACTION_FOUND.equals(action)){
BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
devices.add(device);
String s = "";
for(int a = 0; a < pairedDevices.size(); a++){
if(device.getName().equals(pairedDevices.get(a))){
//append
s = "(Paired)";
break;
}
}
listAdapter.add(device.getName()+" "+s+" "+"\n"+device.getAddress());
}
else if(BluetoothAdapter.ACTION_DISCOVERY_STARTED.equals(action)){
// run some code
}
else if(BluetoothAdapter.ACTION_DISCOVERY_FINISHED.equals(action)){
// run some code
}
else if(BluetoothAdapter.ACTION_STATE_CHANGED.equals(action)){
if(btAdapter.getState() == btAdapter.STATE_OFF){
turnOnBT();
}
}
}
};
registerReceiver(receiver, filter);
filter = new IntentFilter(BluetoothAdapter.ACTION_DISCOVERY_STARTED);
registerReceiver(receiver, filter);
filter = new IntentFilter(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);
registerReceiver(receiver, filter);
filter = new IntentFilter(BluetoothAdapter.ACTION_STATE_CHANGED);
registerReceiver(receiver, filter);
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
// TODO Auto-generated method stub
super.onActivityResult(requestCode, resultCode, data);
if(resultCode == RESULT_CANCELED){
Toast.makeText(getApplicationContext(), "Bluetooth must be enabled to continue", Toast.LENGTH_SHORT).show();
finish();
}
}
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3) {
// TODO Auto-generated method stub
if(btAdapter.isDiscovering()){
btAdapter.cancelDiscovery();
}
if(listAdapter.getItem(arg2).contains("Paired")){
BluetoothDevice selectedDevice = devices.get(arg2);
ConnectThread connect = new ConnectThread(selectedDevice);
connect.start();
Log.i(tag, "in click listener");
}
else{
Toast.makeText(getApplicationContext(), "device is not paired", Toast.LENGTH_LONG).show();
}
}
public class ConnectThread extends Thread {
private final BluetoothSocket mmSocket;
private final BluetoothDevice mmDevice;
public ConnectThread(BluetoothDevice device) {
BluetoothSocket tmp = null;
mmDevice = device;
Log.i(tag, "construct");
try {
tmp = device.createRfcommSocketToServiceRecord(MY_UUID);
} catch (IOException e) {
Log.i(tag, "get socket failed");
}
mmSocket = tmp;
}
public void run() {
btAdapter.cancelDiscovery();
Log.i(tag, "connect - run");
try {
mmSocket.connect();
Log.i(tag, "connect - succeeded");
} catch (IOException connectException) { Log.i(tag, "connect failed");
try {
mmSocket.close();
} catch (IOException closeException) { }
return;
}
mHandler.obtainMessage(SUCCESS_CONNECT, mmSocket).sendToTarget();
}
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) { }
}
}
public 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) { }
mmInStream = tmpIn;
mmOutStream = tmpOut;
}
public void run() {
byte[] buffer; // 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
buffer = new byte[1024];
bytes = mmInStream.read(buffer);
// Send the obtained bytes to the UI activity
mHandler.obtainMessage(MESSAGE_READ, bytes, -1, buffer)
.sendToTarget();
Log.i(tag, "Message Received");
} catch (IOException e) {
break;
}
}
}
/* Call this from the main activity to send data to the remote device */
public void write(byte[] 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) { }
}
}
public void BTwrite(String s){
Log.i(Tag, "Sending over Bluetooth");
sendThread.write(s.getBytes());
s = System.getProperty("line.separator");
sendThread.write(s.getBytes());
Log.i(Tag, "Bluetooth write sent.");
}
public void onBackPressed() {
finish();
}
public void onDestroy() {
super.onDestroy();
finish();
}
}
Here is the call from Main activity
BT.BTwrite("2");
Here is the error I receive
java.lang.NullPointerException: Attempt to invoke virtual method 'void logit.dot.BTadapter$ConnectedThread.write(byte[])' on a null object reference
at logit.dot.BTadapter.BTwrite(BTadapter.java:382)
at logit.dot.Main.insert(Main.java:1016)
at logit.dot.Main.access$4400(Main.java:54)
at logit.dot.Main$13.onClick(Main.java:1233)
at com.android.internal.app.AlertController$ButtonHandler.handleMessage(AlertController.java:165)
at android.os.Handler.dispatchMessage(Handler.java:111)
at android.os.Looper.loop(Looper.java:194)
at android.app.ActivityThread.main(ActivityThread.java:5576)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:955)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:750)

Try to make the bluetoothSocket as a static object. So you will init it once time and call it like MainActivity.bluetoothSocket. Then you can work as you like ,it's like you have a shared object between class.

Can't establish Bluetooth connection between my app and remote Bluetooth HC-05

I'm developing an Android app that is a kind of a remote control (that works via bluetooth) for one Arduino device. I've already could pair my phone with remote Bluetooth. Also it seems that I could establish connection which I've checked with an ACTION_ACL_CONNECTED state like this:
private final BroadcastReceiver connectedReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if (BluetoothDevice.ACTION_ACL_CONNECTED.equals(action)) {
showToast("Conneeeeeeeeeeeeected");
}
}
};
The problem is when I press a button on my app to send some data to the remote Bluetooth, nothing happens (a LED must change its state from OFF to ON). Could you please check what's wrong, maybe it's something with my ConnectThread? Here is my code:
public class MainActivity extends AppCompatActivity {
private final static UUID MY_UUID = UUID.fromString("ecff8f1a-ac66-11e6-80f5-76304dec7eb7");
BluetoothSocket mmSocket;
Button whiteBtn; // after clicking this button, data from my phone are send to remote bluetooth
whiteBtn = (Button) findViewById(R.id.white_btn);
whiteBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
whiteBtnOn();
}
});
#Override
protected void onCreate(Bundle savedInstanceState) {
// Get Bluetooth Adapter
mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (mBluetoothAdapter == null) {
showToast("Bluetooth is not supported on this device");
}
// Enable Bluetooth
if (!mBluetoothAdapter.isEnabled()) {
Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
}
mPairedDevicesArrayAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, arrListPaired);
pairedListView.setAdapter(mPairedDevicesArrayAdapter);
// Find out which devices have been already paired
Set<BluetoothDevice> pairedDevices = mBluetoothAdapter.getBondedDevices();
if (pairedDevices.size() > 0) {
showToast("Paired devices have been found");
// Loop through the paired devices
for (BluetoothDevice device : pairedDevices) {
arrListPaired.add(device.getName() + '\n' + device.getAddress());
mPairedDevicesArrayAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, arrListPaired);
}
pairedListView.setAdapter(mPairedDevicesArrayAdapter);
}
// Click event for items from paired devices list (Possible actions: “Connect”, which establishes connection between my phone and remote Bluetooth, “Unpair”, “Cancel”)
pairedListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, final View view, final int position, long id) {
final String info = ((TextView) view).getText().toString();
int address = info.indexOf(":");
final String adr = info.substring(address - 2, info.length());
final int positionToRemove = position;
final AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
builder.setMessage("What should we do?");
//builder.setMessage("Unpair this device?");
builder.setPositiveButton("Unpair", new OnClickListener() {
#Override
public void onClick(DialogInterface dialogInterface, int i) {
BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(adr);
// UNPAIR DEVICES
unpair(device);
arrListPaired.remove(positionToRemove);
mPairedDevicesArrayAdapter.notifyDataSetChanged();
// END UNPAIR DEVICES
}
});
builder.setNeutralButton("Cancel", new OnClickListener() {
#Override
public void onClick(DialogInterface dialogInterface, int i) {
dialogInterface.cancel();
}
});
// Establish Connection between devices
builder.setNegativeButton("Connect", new OnClickListener() {
#Override
public void onClick(DialogInterface dialogInterface, int i) {
showToast("Establish connection");
BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(adr);
ConnectThread ct = new ConnectThread(device);
ct.start();
IntentFilter filter = new IntentFilter();
filter.addAction(BluetoothDevice.ACTION_ACL_CONNECTED);
registerReceiver(connectedReceiver, filter);
}
});
AlertDialog alertDialog = builder.create();
alertDialog.show();
}
});
#Override
protected void onPause() {
if (mBluetoothAdapter != null) {
if (mBluetoothAdapter.isDiscovering()) {
mBluetoothAdapter.cancelDiscovery();
}
}
super.onPause();
}
#Override
protected void onDestroy() {
unregisterReceiver(mReceiver);
super.onDestroy();
}
private void showToast(String message) {
Toast.makeText(getApplicationContext(), message, Toast.LENGTH_SHORT).show();
}
private void pairDevice(BluetoothDevice device) {
try {
IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_BOND_STATE_CHANGED);
registerReceiver(receiver, filter);
Method method = device.getClass().getMethod("createBond", (Class[]) null);
method.invoke(device, (Object[]) null);
} catch (Exception e) {
e.printStackTrace();
}
}
private void unpair(BluetoothDevice device) {
showToast("Unpaired button is clicked");
try {
if(mmSocket!=null) {mmSocket.close();}
Method m = device.getClass().getMethod("removeBond", (Class[]) null);
m.invoke(device, (Object[]) null);
} catch (NoSuchMethodException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
// Connecting threat
private class ConnectThread extends Thread {
private final BluetoothDevice mmDevice;
public ConnectThread(BluetoothDevice device) {
BluetoothSocket tmp = null;
mmDevice = device;
try {
tmp = device.createRfcommSocketToServiceRecord(MY_UUID);
} catch (IOException e) {}
mmSocket = tmp;
}
public void run () {
mBluetoothAdapter.cancelDiscovery();
try {
mmSocket.connect();
} catch (IOException connectException) {
try {
mmSocket.close();
} catch (IOException closeException) {}
return;
}
//manageConnectedSocket(mmSocket);
}
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) {}
}
}
// Managing a connection
// Broadcast receiver for connected device
private final BroadcastReceiver connectedReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if (BluetoothDevice.ACTION_ACL_CONNECTED.equals(action)) {
showToast("Conneeeeeeeeeeeeected");
}
}
};
// Send data after clicking on a button
private void whiteBtnOn() {
if (mmSocket != null) {
showToast("White btn is clicked");
try {
mmSocket.getOutputStream().write("TO".toString().getBytes());
}
catch (IOException e) {}
}
}
}
}
Thanks in advance for your suggestions!

Try use UUID for Bluetooth SPP:
private final static UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805f9b34fb");
instead of:
private final static UUID MY_UUID = UUID.fromString("ecff8f1a-ac66-11e6-80f5-76304dec7eb7");

Bluetooth android app Rfcomm connection

I wanted to start with the basics of bluetooth connection and make a simple app capable of scanning, pairing and connecting.
I'm struggling with the last concept, i followed a lot of tutorials but I couldn't make it. I don't know if you can help me but here is my code.
ublic class MainActivity extends Activity {
private final String TAG = "Debugging";
private final static int REQUEST_CODE_ENABLE_BLUETOOTH = 0;
protected static final int SUCCESS_CONNECT = 0;
protected static final int MESSAGE_READ = 1;
public static final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
BluetoothAdapter btAdapter;
ArrayList<String> arrayListpaired;
ArrayAdapter<String> listAdapter,adapter;
ListView listView,listViewPaired;
Set<BluetoothDevice> deviceArray;
ArrayList<String> pairedDevices;
IntentFilter filter;
BroadcastReceiver receiver;
BluetoothDevice bdDevice;
ArrayList<BluetoothDevice> arrayListBluetoothDevices = null;
ArrayList<BluetoothDevice> arrayListPairedBluetoothDevices;
ListItemClicked listItemClicked;
ListItemClickedonPaired listItemClickedonPaired;
String tag = "debugging";
Handler mHandler= new Handler() {
public void handleMessage(Message msg){
super.handleMessage(msg);
switch(msg.what){
case SUCCESS_CONNECT:
ConnectedThread connectedThread = new ConnectedThread((BluetoothSocket)msg.obj);
Toast.makeText(getApplicationContext(),"Connect",Toast.LENGTH_LONG).show();
String s= "Succesfully connected";
connectedThread.write(s.getBytes());
Log.i(tag, "connected");
break;
case MESSAGE_READ:
byte[] readbuff=(byte[])msg.obj;
String string= readbuff.toString();
Toast.makeText(getApplicationContext(), string,Toast.LENGTH_SHORT).show();
break;
}
}
};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btAdapter = BluetoothAdapter.getDefaultAdapter();
arrayListBluetoothDevices = new ArrayList<BluetoothDevice>();
arrayListpaired = new ArrayList<String>();
arrayListPairedBluetoothDevices = new ArrayList<BluetoothDevice>();
adapter= new ArrayAdapter<String>(MainActivity.this, android.R.layout.simple_list_item_1, arrayListpaired);
listItemClickedonPaired = new ListItemClickedonPaired();
listViewPaired = (ListView) findViewById(R.id.listView3);
listItemClicked = new ListItemClicked();
listView = (ListView) findViewById(R.id.listView2);
listAdapter = new ArrayAdapter<String>(MainActivity.this, android.R.layout.simple_list_item_activated_1);
listView.setAdapter(listAdapter);
listAdapter.notifyDataSetChanged();
listViewPaired.setAdapter(adapter);
setupMessageButton1();
setupMessageButton2();
setupMessageButton3();
setupMessageButton4();
setupMessageButton5();
init();
getPairedDevices();
}
private void init() {
listView.setOnItemClickListener(listItemClicked);
listViewPaired.setOnItemClickListener(listItemClickedonPaired);
filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);
receiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
String Action = intent.getAction();
if (BluetoothDevice.ACTION_FOUND.equals(Action)) {
Toast.makeText(getApplicationContext(), "One Device Found", Toast.LENGTH_SHORT).show();
BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
if (arrayListBluetoothDevices.size() < 1) // this checks if the size of bluetooth device is 0,then add the
{ // device to the arraylist.
listAdapter.add(device.getName() + "\n" + device.getAddress());
arrayListBluetoothDevices.add(device);
listAdapter.notifyDataSetChanged();
}
else
{
boolean flag = true; // flag to indicate that particular device is already in the arlist or not
for (int i = 0; i < arrayListBluetoothDevices.size(); i++) {
if (device.getAddress().equals(arrayListBluetoothDevices.get(i).getAddress())) {
flag = false;
}
}
if (flag == true) {
listAdapter.add(device.getName() + "\n" + device.getAddress());
arrayListBluetoothDevices.add(device);
listAdapter.notifyDataSetChanged();
}
}
}
}
};
registerReceiver(receiver, filter);
}
private void createBond(BluetoothDevice btDevice){
try
{
Method method = btDevice.getClass().getMethod("createBond", (Class[]) null);
method.invoke(btDevice, (Object[]) null);
}
catch (Exception e)
{
e.printStackTrace();
}
}
private void unpairDevice(BluetoothDevice device) {
try {
Method method = device.getClass().getMethod("removeBond", (Class[]) null);
method.invoke(device, (Object[]) null);
} catch (Exception e) {
e.printStackTrace();
}
}
private void getPairedDevices() {
Set<BluetoothDevice> pairedDevice = btAdapter.getBondedDevices();
if(pairedDevice.size()>0)
{
for(BluetoothDevice device : pairedDevice)
{
arrayListpaired.add(device.getName()+"\n"+device.getAddress());
arrayListPairedBluetoothDevices.add(device);
}
}
adapter.notifyDataSetChanged();
}
public class ListItemClicked implements OnItemClickListener {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
// TODO Auto-generated method stub
bdDevice = arrayListBluetoothDevices.get(position);
Log.i("Log", "The device : " + bdDevice.toString());
getPairedDevices();
createBond(bdDevice);
adapter.notifyDataSetChanged();
Log.i("Log", "The bond is created: with" + bdDevice.toString());
}
}
private class ConnectThread extends Thread {
private final BluetoothSocket mmSocket;
private final BluetoothDevice mmDevice;
public ConnectThread(BluetoothDevice device) {
BluetoothSocket tmp = null;
mmDevice = device;
try {
tmp = device.createRfcommSocketToServiceRecord(MY_UUID);
} catch (IOException e) { }
mmSocket = tmp;
}
public void run() {
btAdapter.cancelDiscovery();
try {
mmSocket.connect();
} catch (IOException connectException) {
try {
mmSocket.close();
} catch (IOException closeException) { }
return;
}
mHandler.obtainMessage(SUCCESS_CONNECT, mmSocket).sendToTarget();
}
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) { }
}
}
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; // 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
buffer = new byte[1024];
bytes = mmInStream.read(buffer);
// Send the obtained bytes to the UI activity
mHandler.obtainMessage(MESSAGE_READ, bytes, -1, buffer)
.sendToTarget();
} catch (IOException e) {
break;
}
}
}
/* Call this from the main activity to send data to the remote device */
public void write(byte[] 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) { }
}
}
#Override
protected void onDestroy() {
super.onDestroy();
btAdapter.cancelDiscovery();
unregisterReceiver(receiver);
}
class ListItemClickedonPaired implements OnItemClickListener
{
#Override
public void onItemClick(AdapterView<?> parent, View view, int position,long id) {
bdDevice = arrayListPairedBluetoothDevices.get(position);
unpairDevice(bdDevice);
//arrayListPairedBluetoothDevices.clear();
}
}
private void makeDiscoverable() {
Intent discoverableIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_DISCOVERABLE);
discoverableIntent.putExtra(BluetoothAdapter.EXTRA_DISCOVERABLE_DURATION, 150);
startActivity(discoverableIntent);
}
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == RESULT_CANCELED) {
Toast.makeText(MainActivity.this, "Bluetooth must be enabled to start scanning", Toast.LENGTH_SHORT).show();
} else
{
Toast.makeText(MainActivity.this, "Click on TURN_OFF to disable bluetooth", Toast.LENGTH_LONG).show();
}
}
private void setupMessageButton1() {
//1.get a reference for my button
Button messageButton = (Button) findViewById(R.id.button1);
//2. Set the click to run my code
messageButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
listAdapter.clear();
arrayListBluetoothDevices.clear();
btAdapter.startDiscovery();
}
});
}
private void setupMessageButton2() {
//1.get a reference to the button.
Button messageButton = (Button) findViewById(R.id.button2);
//2. set the click listener to run my code.
messageButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (btAdapter.isEnabled()) {
listAdapter.clear();
btAdapter.disable();
} else
{
Toast.makeText(MainActivity.this, "Dont worry it's already off", Toast.LENGTH_SHORT).show();
}
}
});
}
private void setupMessageButton3() {
//1.get a reference for my button
Button messageButton = (Button) findViewById(R.id.button3);
//2. Set the click to run my code
messageButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
finish();
}
});
}
private void setupMessageButton4() {
//1.get a reference for my button
Button messageButton = (Button) findViewById(R.id.button4);
//2. Set the click to run my code
messageButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
btAdapter.enable();
}
});
}
private void setupMessageButton5() {
//1.get a reference for my button
Button messageButton = (Button) findViewById(R.id.button5);
//2. Set the click to run my code
messageButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
makeDiscoverable();
}
});
}
}
Concerning the log i have that message :
"D/BluetoothUtils﹕ isSocketAllowedBySecurityPolicy start : device null"
"W/BluetoothAdapter﹕ getBluetoothService() called with no BluetoothManagerCallback"
"D/BluetoothSocket﹕ connect(), SocketState: INIT, mPfd: {ParcelFileDescriptor: FileDescriptor[75]} "
public class ListItemClicked implements OnItemClickListener {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
// TODO Auto-generated method stub
bdDevice = arrayListBluetoothDevices.get(position);
Log.i("Log", "The device : " + bdDevice.toString());
createBond(bdDevice);
adapter.notifyDataSetChanged();
ConnectThread connect = new ConnectThread(bdDevice);
connect.start();
}
}
For the connection, i use the ConnectThread found in Bluetooth APi developer Website:
private class ConnectThread extends Thread {
private final BluetoothSocket mmSocket;
private final BluetoothDevice mmDevice;
public ConnectThread(BluetoothDevice device) {
BluetoothSocket tmp = null;
mmDevice = device;
try {
tmp = device.createRfcommSocketToServiceRecord(MY_UUID);
} catch (IOException e) { }
mmSocket = tmp;
}
public void run() {
btAdapter.cancelDiscovery();
try {
mmSocket.connect();
} catch (IOException connectException) {
try {
mmSocket.close();
} catch (IOException closeException) { }
return;
}
mHandler.obtainMessage(SUCCESS_CONNECT, mmSocket).sendToTarget();
}
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) { }
}
}

it's ok i found the solution, i had the problem with the phone i'm using, he is not supporting SPP.
Thank you anyway

how to know android device version or API via bluetooth

hi everyone,
In my application i want to send data only 2.3.3 and above android deceives but when i start discover Bluetooth devices my application get all activated devices .
Those devices are both android and other devices.How can i filter or know about devices who have 2.3.3 or above version
my code give below:
public class MainActivity extends Activity implements OnItemClickListener {
Button mBtnConnect;
ListView mlist;
BluetoothAdapter mBluetoothAdapter;
IntentFilter filter;
MyBluetoothAdapter blu_adapter=null;
Set<BluetoothDevice> deviceArray;
ArrayList<String> pairedDevices;
ArrayList<String> pairedDevices_list;
ArrayList<String> bonded_list;
ArrayList<BluetoothDevice> Devices;
public static final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805f9b34fb");
protected static final int SUCCESS_CONNECT = 0;
protected static final int MESSAGE_READ=1;
Handler mHandler=new Handler() {
public void handleMessage(Message msg) {
super.handleMessage(msg);
switch (SUCCESS_CONNECT) {
case SUCCESS_CONNECT:
ConnectedThread connecteThread=new ConnectedThread((BluetoothSocket)msg.obj);
Toast.makeText(getApplicationContext(), "Connected", 0).show();
String s="successfully connected ";
connecteThread.write(s.getBytes());
break;
case MESSAGE_READ:
byte[] readBuf=(byte[]) msg.obj;
String string =new String(readBuf);
Toast.makeText(getApplicationContext(), string, 0).show();
break;
}
}
};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initilizeField();
if (mBluetoothAdapter == null) {
Toast.makeText(getApplicationContext(),
"No bluetooth device found", 0).show();
finish();
}
else {
if (!mBluetoothAdapter.isEnabled()) {
TurnonBT();
}
getPairedDevices();
StartDiscovery();
}
mBtnConnect.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
blu_adapter=new MyBluetoothAdapter(MainActivity.this, pairedDevices,bonded_list);
mlist.setAdapter(blu_adapter);
}
});
}
private void StartDiscovery() {
// TODO Auto-generated method stub
mBluetoothAdapter.cancelDiscovery();
mBluetoothAdapter.startDiscovery();
}
private void TurnonBT() {
// TODO Auto-generated method stub
Intent enableBluetooth = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBluetooth, 1);
}
private void initilizeField() {
// TODO Auto-generated method stub
mlist = (ListView) findViewById(R.id.listView);
mBtnConnect = (Button) findViewById(R.id.mBtnConnect);
mlist = (ListView) findViewById(R.id.listView);
pairedDevices = new ArrayList<String>();
pairedDevices_list = new ArrayList<String>();
bonded_list=new ArrayList<String>();
Devices=new ArrayList<BluetoothDevice>();
/*listAdapter = new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1, 0);
mlist.setAdapter(listAdapter);*/
//click listner
mlist.setOnItemClickListener(this);
mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
Intent discoverableIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_DISCOVERABLE);
discoverableIntent.putExtra(BluetoothAdapter.EXTRA_DISCOVERABLE_DURATION, 400);
startActivity(discoverableIntent);
Toast.makeText(getApplicationContext(), "Now your device is discoverable by others", Toast.LENGTH_LONG).show();
filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);
registerReceiver(receiver, filter);
filter = new IntentFilter(BluetoothAdapter.ACTION_DISCOVERY_STARTED);
registerReceiver(receiver, filter);
filter = new IntentFilter(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);
registerReceiver(receiver, filter);
filter = new IntentFilter(BluetoothAdapter.ACTION_STATE_CHANGED);
registerReceiver(receiver, filter);
// deviceArray=new
}
BroadcastReceiver receiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
// TODO Auto-generated method stub
String action = intent.getAction();
if (BluetoothDevice.ACTION_FOUND.equals(action)) {
BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
Devices.add(device);
//- listAdapter.add(device.getName() + " "+s+" "+"\n"+ device.getAddress());
for (BluetoothDevice devicePaired : Devices) {
if(bonded_list.contains(devicePaired)){
}
else{
bonded_list.add("Not Paired");
}
}
if(pairedDevices.contains(device.getName())){
}
else{
pairedDevices.add(device.getName());
}
} else if (BluetoothAdapter.ACTION_DISCOVERY_STARTED.equals(action)) {
} else if (BluetoothAdapter.ACTION_DISCOVERY_FINISHED.equals(action)) {
/* if(listAdapter.getCount()>0){
for(int i=0;i<listAdapter.getCount();i++){
for(int a=0;a<pairedDevices.size();a++){
if(listAdapter.getItem(i).equals(pairedDevices.get(a))){
}
}
}
}*/
} else if (BluetoothAdapter.ACTION_STATE_CHANGED.equals(action)) {
if(mBluetoothAdapter.getState()==mBluetoothAdapter.STATE_OFF){
TurnonBT();
}
}
}
};
private void getPairedDevices() {
// TODO Auto-generated method stub
deviceArray = mBluetoothAdapter.getBondedDevices();
if (deviceArray.size() > 0) {
for (BluetoothDevice device : deviceArray) {
if(pairedDevices.contains(device.getName())){
//device already in paired array list
}
else{
pairedDevices.add(device.getName());
bonded_list.add("Paired");
}
}
}
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
// TODO Auto-generated method stub
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == RESULT_CANCELED) {
Toast.makeText(getApplicationContext(),
"Bluetooth must be enable to connect", Toast.LENGTH_SHORT)
.show();
finish();
}
}
#Override
protected void onPause() {
// TODO Auto-generated method stub
super.onPause();
getPairedDevices();
StartDiscovery();
/*filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);
registerReceiver(receiver, filter);
filter = new IntentFilter(BluetoothAdapter.ACTION_DISCOVERY_STARTED);
registerReceiver(receiver, filter);
filter = new IntentFilter(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);
registerReceiver(receiver, filter);
filter = new IntentFilter(BluetoothAdapter.ACTION_STATE_CHANGED);
registerReceiver(receiver, filter);*/
//unregisterReceiver(receiver);
}
#Override
protected void onDestroy() {
super.onDestroy();
if (mBluetoothAdapter != null) {
mBluetoothAdapter.cancelDiscovery();
}
unregisterReceiver(receiver);
}
#Override
public void onItemClick(AdapterView<?> arg0, View arg1, int position, long arg3) {
// TODO Auto-generated method stub
if(mBluetoothAdapter.isDiscovering()){
mBluetoothAdapter.cancelDiscovery();
}
if(bonded_list.get(position).contains("Paired")){
//Toast.makeText(getApplicationContext(), "This device is already paired", 0).show();
//Object[] o=deviceArray.toArray();
BluetoothDevice selectedDevices=Devices.get(position);
ConnectThread connect=new ConnectThread(selectedDevices);
connect.start();
}
else{
Toast.makeText(getApplicationContext(), "This device is Not paired", 0).show();
}
}
private class ConnectThread extends Thread {
private final BluetoothSocket mmSocket;
private final BluetoothDevice mmDevice;
public ConnectThread(BluetoothDevice device) {
// Use a temporary object that is later assigned to mmSocket,
// because mmSocket is final
BluetoothSocket tmp = null;
mmDevice = device;
// Get a BluetoothSocket to connect with the given BluetoothDevice
try {
// MY_UUID is the app's UUID string, also used by the server code
tmp = device.createRfcommSocketToServiceRecord(MY_UUID);
} catch (IOException e) { }
mmSocket = tmp;
}
public void run() {
// Cancel discovery because it will slow down the connection
mBluetoothAdapter.cancelDiscovery();
try {
// Connect the device through the socket. This will block
// until it succeeds or throws an exception
mmSocket.connect();
} catch (IOException connectException) {
// Unable to connect; close the socket and get out
try {
mmSocket.close();
} catch (IOException closeException) { }
return;
}
// Do work to manage the connection (in a separate thread)
// manageConnectedSocket(mmSocket);
mHandler.obtainMessage(SUCCESS_CONNECT,mmSocket).sendToTarget();
}
private void manageConnectedSocket(BluetoothSocket mmSocket2) {
// TODO Auto-generated method stub
}
/** Will cancel an in-progress connection, and close the socket */
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) { }
}
}
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; // 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
buffer= new byte[1024];
bytes = mmInStream.read(buffer);
// Send the obtained bytes to the UI activity
mHandler.obtainMessage(MESSAGE_READ, bytes, -1, buffer)
.sendToTarget();
} catch (IOException e) {
break;
}
}
}
/* Call this from the main activity to send data to the remote device */
public void write(byte[] 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) { }
}
}
}

int currentapiVersion = android.os.Build.VERSION.SDK_INT;
if (currentapiVersion >= android.os.Build.VERSION_CODES.FROYO){
// Do something for froyo and above versions
} else{
// do something for phones running an SDK before froyo
}

Develop Reference

The Android operating system is a mobile operating system that was developed by Google (GOOGL?) to be primarily used for touchscreen devices, cell phones, and tablets.

connecting paired devices in Bluetooth using android studio - android

Related

Android Studio Bluetooth ListView

How do I send Bluetooth data from another activity outside of Bluetooth class

Can't establish Bluetooth connection between my app and remote Bluetooth HC-05

Bluetooth android app Rfcomm connection

how to know android device version or API via bluetooth

Categories

Resources