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change text color with spannable

In the below code which is for bluetooth messaging with arduino i am trying to change color on some static strings.
1.On the start button listener i have a message"Connection opened" which i am changing color using the xml file and creating there a string with specific color. This method works only there.
2. i tried another method with spannable string on the send button listener but is not working at all the message comes in black.
what i want to to do is that when i send a message on my textview i see the "send data: "+ string(msg i send) and i want this send data to be red for examle and the same for the receive one.
What i tried untill now is on the code.If there is any idea to try i will be grateful.
public class MainActivity extends Activity {
private final UUID PORT_UUID = UUID.fromString("00001101-0000-1000-8000-00805f9b34fb");//Serial Port Service ID
private BluetoothDevice device;
private BluetoothSocket socket;
private OutputStream outputStream;
private InputStream inputStream;
Button startButton, sendButton,clearButton,stopButton;
TextView textView;
EditText editText;
boolean deviceConnected=false;
//Thread thread;
byte[] buffer;
//int bufferPosition;
boolean stopThread;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
startButton = findViewById(R.id.buttonStart);
sendButton = findViewById(R.id.buttonSend);
clearButton = findViewById(R.id.buttonClear);
stopButton = findViewById(R.id.buttonStop);
editText = findViewById(R.id.editText);
textView = findViewById(R.id.textView);
textView.setMovementMethod(new ScrollingMovementMethod());
setUiEnabled(false);
startButton.setOnClickListener(v -> {
if(BTinit())
{
if(BTconnect())
{
setUiEnabled(true);
deviceConnected=true;
beginListenForData();
//textView.append("Connection Opened!");
String greenString = getResources().getString(R.string.Connection_Opened);
textView.append(Html.fromHtml(greenString));
}
}
});
sendButton.setOnClickListener(v -> {
String t = "Send Data: ";
SpannableString spannableString = new SpannableString(t);
ForegroundColorSpan green = new ForegroundColorSpan(getResources().getColor(R.color.private_green));
spannableString.setSpan(green, 0, 9, Spanned.SPAN_INCLUSIVE_INCLUSIVE);
String string = editText.getText().toString();
String str = string.concat("\n");
try {
outputStream.write(str.getBytes());
} catch (IOException e) {
e.printStackTrace();
}
textView.append(spannableString + str);
});
stopButton.setOnClickListener(v -> {
try {
stopThread = true;
outputStream.close();
inputStream.close();
socket.close();
setUiEnabled(false);
deviceConnected=false;
textView.append("Connection Closed!");
}catch (IOException e){
e.printStackTrace();
}
});
clearButton.setOnClickListener(v -> textView.setText(""));
}
public void setUiEnabled(boolean bool)
{
startButton.setEnabled(!bool);
sendButton.setEnabled(bool);
stopButton.setEnabled(bool);
textView.setEnabled(bool);
}
public boolean BTinit()
{
boolean found=false;
BluetoothAdapter bluetoothAdapter=BluetoothAdapter.getDefaultAdapter();
if (bluetoothAdapter == null) {
Toast.makeText(getApplicationContext(),"Device doesnt Support Bluetooth",Toast.LENGTH_SHORT).show();
}
if(bluetoothAdapter !=null)
{
Intent enableAdapter = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableAdapter, 0);
}
assert bluetoothAdapter != null;
Set<BluetoothDevice> bondedDevices = bluetoothAdapter.getBondedDevices();
if(bondedDevices.isEmpty())
{
Toast.makeText(getApplicationContext(),"Please Pair the Device first",Toast.LENGTH_SHORT).show();
}
else
{
for (BluetoothDevice iterator : bondedDevices)
{
//private final String DEVICE_NAME="ArduinoBT";
String DEVICE_ADDRESS = "98:DA:C0:00:2C:E2";
if(iterator.getAddress().equals(DEVICE_ADDRESS))
{
device=iterator;
found=true;
break;
}
}
}
return found;
}
public boolean BTconnect()
{
boolean connected=true;
try {
socket = device.createRfcommSocketToServiceRecord(PORT_UUID);
socket.connect();
} catch (IOException e) {
e.printStackTrace();
connected=false;
}
if(connected)
{
try {
outputStream=socket.getOutputStream();
} catch (IOException e) {
e.printStackTrace();
}
try {
inputStream=socket.getInputStream();
} catch (IOException e) {
e.printStackTrace();
}
}
return connected;
}
void beginListenForData()
{
final Handler handler = new Handler();
stopThread = false;
buffer = new byte[1024];
Thread thread = new Thread(() -> {
while(!Thread.currentThread().isInterrupted() && !stopThread)
{
try
{
int byteCount = inputStream.available();
if(byteCount > 0)
{
byte[] rawBytes = new byte[byteCount];
inputStream.read(rawBytes);
final String string=new String(rawBytes, StandardCharsets.UTF_8);
handler.post(() -> textView.append("Receive data: " + string));
}
}
catch (IOException ex)
{
stopThread = true;
}
}
});
thread.start();
}
}

Try like this;
Spannable text = new SpannableString("Send Data:");
text.setSpan(new ForegroundColorSpan(getResources().getColor(R.color.private_green)), 0, 9, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);

Error in socket.connect() in Android Bluetooth

I am new to Android programming. I am trying to connect two android mobiles through bluetooth. I am using android 4.4.4 in one mobile and android 6 in another. And I am using Windows 7, Android Studio.
Code-
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Button openButton = (Button)findViewById(R.id.open);
Button sendButton = (Button)findViewById(R.id.send);
Button closeButton = (Button)findViewById(R.id.close);
myLabel = (TextView)findViewById(R.id.label);
myTextbox = (EditText)findViewById(R.id.entry);
//Open Button
openButton.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v)
{
try
{
findBT();
openBT();
}
catch (IOException ex) { }
}
});
//Send Button
sendButton.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v)
{
try
{
sendData();
}
catch (IOException ex) { }
}
});
//Close button
closeButton.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v)
{
try
{
closeBT();
}
catch (IOException ex) { }
}
});
}
void findBT()
{
mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if(mBluetoothAdapter == null)
{
myLabel.setText("No bluetooth adapter available");
}
if(!mBluetoothAdapter.isEnabled())
{
Intent enableBluetooth = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBluetooth, 0);
}
Set<BluetoothDevice> pairedDevices = mBluetoothAdapter.getBondedDevices();
if(pairedDevices.size() > 0)
{
for(BluetoothDevice device : pairedDevices)
{
if(device.getName().equals("motoG"))
{
mmDevice = device;
break;
}
}
}
myLabel.setText("Bluetooth Device Found");
}
void openBT() throws IOException
{
UUID uuid = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB"); //Standard SerialPortService ID
mmSocket = mmDevice.createRfcommSocketToServiceRecord(uuid);
mBluetoothAdapter.cancelDiscovery();
mmSocket.connect();
mmOutputStream = mmSocket.getOutputStream();
mmInputStream = mmSocket.getInputStream();
beginListenForData();
myLabel.setText("Bluetooth Opened");
}
void beginListenForData()
{
final Handler handler = new Handler();
final byte delimiter = 10; //This is the ASCII code for a newline character
stopWorker = false;
readBufferPosition = 0;
readBuffer = new byte[1024];
workerThread = new Thread(new Runnable()
{
public void run()
{
while(!Thread.currentThread().isInterrupted() && !stopWorker)
{
try
{
int bytesAvailable = mmInputStream.available();
if(bytesAvailable > 0)
{
byte[] packetBytes = new byte[bytesAvailable];
mmInputStream.read(packetBytes);
for(int i=0;i<bytesAvailable;i++)
{
byte b = packetBytes[i];
if(b == delimiter)
{
byte[] encodedBytes = new byte[readBufferPosition];
System.arraycopy(readBuffer, 0, encodedBytes, 0, encodedBytes.length);
final String data = new String(encodedBytes, "US-ASCII");
readBufferPosition = 0;
handler.post(new Runnable()
{
public void run()
{
myLabel.setText(data);
}
});
}
else
{
readBuffer[readBufferPosition++] = b;
}
}
}
}
catch (IOException ex)
{
stopWorker = true;
}
}
}
});
workerThread.start();
}
void sendData() throws IOException
{
String msg = myTextbox.getText().toString();
msg += "\n";
mmOutputStream.write(msg.getBytes());
myLabel.setText("Data Sent");
}
void closeBT() throws IOException
{
stopWorker = true;
mmOutputStream.close();
mmInputStream.close();
mmSocket.close();
myLabel.setText("Bluetooth Closed");
}
}
Error- In .connect(), I am getting an exception -
read failed, socket might closed or timeout, read ret: -1.
getBluetoothService() called with no BluetoothManagerCallback
connect(), SocketState: INIT, mPfd: {ParcelFileDescriptor: FileDescriptor[55]}
I tried using insecureRFcom, it din't work. I re-paired my device, but didn't work. I removed all other paired devices from mobile, it din't work. I looked around this website and tried many approaches, but nothing works. Hope someone can help me figure out the problem.

Not getting proper voltage reading from my OBDII reading app

I'm working on a OBDII reading app to read basic data such as (in this case) voltage. I've tried other apps and it works just fine to read the voltage of the OBDII adapter, so there's nothing wrong with the adapter itself.
I'm using the OBDII api from pires on github. When connection to my OBDII via Bluetooth successfully I get 0,0V and after that I get a Error saying: "Error running 01 42, response: ...UNABLETOCONNECT" (you can see this in the log cat below)
BTHandler.java
public class BTHandler {
public static final int STATE_NONE = 0; // we're doing nothing
public static final int STATE_CONNECTING = 2; // now initiating an outgoing connection
public static final int STATE_CONNECTED = 3; // now connected to a remote device
final ArrayList<String> devices = new ArrayList();
private final Handler mHandler;
private BluetoothAdapter mAdapter;
private BluetoothDevice device;
private ConnectThread mConnectThread;
private ConnectedThread mConnectedThread;
private BluetoothSocket socket;
private String status;
private int pPlatform = Constants.SPA;
private int mState;
private boolean connectionStatus = false;
public BTHandler(Context context, Handler handler) { // Konstruktor
mAdapter = BluetoothAdapter.getDefaultAdapter();
mHandler = handler;
}
public void write(String s) {
mConnectedThread.sendRawCommand(s);
Log.v("write", "write");
}
public void connect(String deviceAddress) {
mConnectThread = new ConnectThread(deviceAddress);
mConnectThread.start();
}
private void guiHandler(int what, int arg1, String obj) {
Message msg = mHandler.obtainMessage();
msg.what = what;
msg.obj = obj;
msg.arg1 = arg1;
msg.sendToTarget();
}
private class ConnectThread extends Thread {
BluetoothSocket tmp = null;
private BluetoothSocket mmSocket;
public ConnectThread(String deviceAddress) {
mAdapter = BluetoothAdapter.getDefaultAdapter();
device = mAdapter.getRemoteDevice(deviceAddress);
BluetoothAdapter mAdapter = BluetoothAdapter.getDefaultAdapter();
BluetoothDevice device = mAdapter.getRemoteDevice(deviceAddress);
UUID uuid = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
try {
tmp = device.createRfcommSocketToServiceRecord(uuid);
//socket.connect();
//Log.v("connect", "connect");
} catch (IOException e) {
//e.printStackTrace();
//Log.v("exception", "e");
}
mmSocket = tmp;
}
public void run() {
// Cancel discovery because it will slow down the connection
mAdapter.cancelDiscovery();
byte[] buffer = new byte[1024]; // buffer store for the stream
int bytes;
try {
// Connect the device through the socket. This will block
// until it succeeds or throws an exception
mmSocket.connect();
Log.v("connect", "connect");
} catch (IOException connectException) {
Log.v("connectException", "e");
try {
mmSocket.close();
Log.v("close", "close");
} catch (IOException closeException) {
Log.v("closeException", "e");
}
guiHandler(Constants.TOAST, Constants.SHORT, "Connection Failed");
return;
}
guiHandler(Constants.CONNECTION_STATUS, Constants.STATE_CONNECTED, "");
mConnectedThread = new ConnectedThread(mmSocket);
mConnectedThread.start();
}
}
private class ConnectedThread extends Thread {
private final InputStream mmInStream;
private final OutputStream mmOutStream;
private BluetoothSocket mmSocket;
private ObdMultiCommand multiCommand;
public ConnectedThread(BluetoothSocket socket) {
connectionStatus = true;
mmSocket = socket;
InputStream tmpIn = null;
OutputStream tmpOut = null;
switch (pPlatform) {
case Constants.SPA:
multiCommand = new ObdMultiCommand();
multiCommand.add(new OdbRawCommand(SPA.VOLTAGE));
break;
}
try {
tmpIn = socket.getInputStream();
tmpOut = socket.getOutputStream();
} catch (IOException e) {
Log.v("e", "e");
}
mmInStream = tmpIn;
mmOutStream = tmpOut;
}
public void run() {
byte[] buffer = new byte[1024]; // buffer store for the stream
int bytes; // bytes returned from read()
OBDcmds();
// Keep listening to the InputStream until an exception occurs
try {
ModuleVoltageCommand voltageCommand = new ModuleVoltageCommand();
while (!Thread.currentThread().isInterrupted()) {
//System.out.println("Inside while");
// TODO handle commands result
Log.d("d", "Voltage: " + voltageCommand.getFormattedResult());
try {
voltageCommand.run(mmInStream, mmOutStream);
voltageCommand.getFormattedResult();
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
System.out.println("inside catch before while");
}
// Get the input and output streams, using temp objects because
// member streams are final
/*
try {
ModuleVoltageCommand voltageCommand = new ModuleVoltageCommand();
while (!Thread.currentThread().isInterrupted()) {
voltageCommand.run(mmSocket.getInputStream(), mmSocket.getOutputStream());
voltageCommand.getFormattedResult();
Log.d("Log", "Voltage:" + voltageCommand.getFormattedResult());
}
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
*/
//ModuleVoltageCommand voltageCommand = new ModuleVoltageCommand();
/*while (!Thread.currentThread().isInterrupted()) {
try {
voltageCommand.run(socket.getInputStream(), socket.getOutputStream());
voltageCommand.getCalculatedResult();
Log.d("Log", "Voltage:" + voltageCommand.getResultUnit());
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}*/
}
private void OBDcmds() { // execute commands
try {
new EchoOffCommand().run(mmInStream, mmOutStream);
new LineFeedOffCommand().run(mmInStream, mmOutStream);
new TimeoutCommand(100).run(mmInStream, mmOutStream);
new SelectProtocolCommand(ObdProtocols.AUTO).run(mmInStream, mmOutStream);
//ISO_15765_4_CAN
} catch (Exception e) {
Log.v("OBDcmds", "e");
// handle errors
}
}
// CALL this to MainActivity
public void sendRawCommand(String s) {
try {
} catch (Exception e) {
Log.v("sendRawCommand", "e");
}
}
/*
// 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) {
}
}
}
}
MainActivity.java
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
Button b1;
BluetoothAdapter mAdapter;
FragmentHostCallback mHost;
BTHandler btHandler;
private Handler mHandler = new Handler() {
#Override
public void handleMessage(Message msg) {
switch (msg.what) {
case Constants.MESSAGE_STATE_CHANGE:
switch (msg.arg1) {
case BTHandler.STATE_CONNECTED:
setContentView(R.layout.activity_connected);
Toast.makeText(getApplicationContext(), R.string.title_connected_to, Toast.LENGTH_SHORT).show();
Log.v("Log", "Connected");
break;
case BTHandler.STATE_NONE:
Toast.makeText(getApplicationContext(), R.string.title_not_connected, Toast.LENGTH_SHORT).show();
break;
}
}
}
};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btHandler = new BTHandler(MainActivity.this, mHandler);
b1 = (Button) findViewById(R.id.connect);
b1.setOnClickListener(this);
mAdapter = BluetoothAdapter.getDefaultAdapter();
//init();
if (mAdapter == null) {
Toast.makeText(getApplicationContext(), R.string.device_not_supported, Toast.LENGTH_LONG).show();
finish();
} else {
if (!mAdapter.isEnabled()) {
Intent intent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(intent, 1);
}
}
//BTHandler btHandler = new BTHandler(MainActivity.this, mHandler);
//btHandler.connect("");
}
public void onClick(View v) {
int id = v.getId();
//String voltage = ("ATRV");
switch (id) {
case R.id.connect:
onConnect(); //Operation
Log.v("Log", "Pressed onClick");
break;
case R.id.getValue:
btHandler.write(SPA.VOLTAGE);
Log.v("getValue","" + SPA.VOLTAGE);
break;
}
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == RESULT_CANCELED) {
Toast.makeText(getApplicationContext(), R.string.enable_bluetooth, Toast.LENGTH_SHORT).show();
finish();
}
}
private void onConnect() {
ArrayList deviceStrs = new ArrayList();
final ArrayList<String> devices = new ArrayList();
BluetoothAdapter mAdapter = BluetoothAdapter.getDefaultAdapter();
Set pairedDevices = mAdapter.getBondedDevices();
if (pairedDevices.size() > 0) {
for (Object device : pairedDevices) {
BluetoothDevice bdevice = (BluetoothDevice) device;
deviceStrs.add(bdevice.getName() + "\n" + bdevice.getAddress());
devices.add(bdevice.getAddress());
}
}
// show list
final AlertDialog.Builder alertDialog = new AlertDialog.Builder(this);
ArrayAdapter adapter = new ArrayAdapter(this, android.R.layout.select_dialog_singlechoice,
deviceStrs.toArray(new String[deviceStrs.size()]));
alertDialog.setSingleChoiceItems(adapter, -1, new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
dialog.dismiss();
int position = ((AlertDialog) dialog).getListView().getCheckedItemPosition();
String deviceAddress = devices.get(position);
btHandler.connect(deviceAddress);
//btHandler.write();
}
});
alertDialog.setTitle("Paired devices");
alertDialog.show();
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
Constants.java
public interface Constants {
int MESSAGE_STATE_CHANGE = 1;
int TOAST = 1;
int SHORT = 0;
int STATE_CONNECTED = 3;
int CONNECTION_STATUS = 1;
int MESSAGE_DEVICE_NAME = 4;
String DEVICE_NAME = "device_name";
int SPA = 1;
}
SPA.java
public interface SPA {
String VOLTAGE = "AT RV";
}

How do I initiate my BluetoothHandler to another (several) activity?

I'm making a OBDII Bluetooth Android app and i'm having some issues sending out commands. I've already made a successfully connection between my mobile device and my OBDII adapter, but when I click on another activity, the Bluetooth connection seems to quit?
When you open up the app you'll see a button that says "Connect Device". When you press that, a ListAdapter will show up with paired Bluetooth devices. Then when you have succesfully connected to the device (OBDII Adapter) it will take you to another layout where there is 3 activities that are 3 different powerplatforms for cars. This is where the problem occurs. For now, I just want to be able to read the voltage from the OBDII. But when I click my button getValue inside one of the 3 activities. I get an logcat error. And I think it's because I haven't initiated my BluetoothHandler properly. I have no idea how to do this.
MainActivity:
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
Button b1;
BluetoothAdapter mAdapter;
FragmentHostCallback mHost;
BTHandler btHandler;
private Handler mHandler = new Handler() {
#Override
public void handleMessage(Message msg) {
switch (msg.what) {
case Constants.MESSAGE_STATE_CHANGE:
switch (msg.arg1) {
case BTHandler.STATE_CONNECTED:
//setContentView(R.layout.activity_connected);
Intent intent = new Intent(MainActivity.this, Connected.class);
startActivity(intent);
Toast.makeText(getApplicationContext(), R.string.title_connected_to, Toast.LENGTH_SHORT).show();
Log.v("Log", "Connected");
break;
case BTHandler.STATE_NONE:
Toast.makeText(getApplicationContext(), R.string.title_not_connected, Toast.LENGTH_SHORT).show();
break;
}
}
}
};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btHandler = new BTHandler(MainActivity.this, mHandler);
b1 = (Button) findViewById(R.id.connect);
b1.setOnClickListener(this);
mAdapter = BluetoothAdapter.getDefaultAdapter();
//init();
if (mAdapter == null) {
Toast.makeText(getApplicationContext(), R.string.device_not_supported, Toast.LENGTH_LONG).show();
finish();
} else {
if (!mAdapter.isEnabled()) {
Intent intent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(intent, 1);
}
}
//BTHandler btHandler = new BTHandler(MainActivity.this, mHandler);
//btHandler.connect("");
}
public void onClick(View v) {
int id = v.getId();
//String voltage = ("ATRV");
switch (id) {
case R.id.connect:
onConnect(); //Operation
Log.v("Log", "Pressed onClick");
break;
/*case R.id.getValue:
btHandler.write(voltage);
Log.v("Log", "getValue" + voltage);
break;*/
}
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == RESULT_CANCELED) {
Toast.makeText(getApplicationContext(), R.string.enable_bluetooth, Toast.LENGTH_SHORT).show();
finish();
}
}
private void onConnect() {
ArrayList deviceStrs = new ArrayList();
final ArrayList<String> devices = new ArrayList();
BluetoothAdapter mAdapter = BluetoothAdapter.getDefaultAdapter();
Set pairedDevices = mAdapter.getBondedDevices();
if (pairedDevices.size() > 0) {
for (Object device : pairedDevices) {
BluetoothDevice bdevice = (BluetoothDevice) device;
deviceStrs.add(bdevice.getName() + "\n" + bdevice.getAddress());
devices.add(bdevice.getAddress());
}
}
// show list
final AlertDialog.Builder alertDialog = new AlertDialog.Builder(this);
ArrayAdapter adapter = new ArrayAdapter(this, android.R.layout.select_dialog_singlechoice,
deviceStrs.toArray(new String[deviceStrs.size()]));
alertDialog.setSingleChoiceItems(adapter, -1, new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
dialog.dismiss();
int position = ((AlertDialog) dialog).getListView().getCheckedItemPosition();
String deviceAddress = devices.get(position);
btHandler.connect(deviceAddress);
//btHandler.write();
}
});
alertDialog.setTitle("Paired devices");
alertDialog.show();
}
BTHandler:
public class BTHandler {
public static final int STATE_NONE = 0; // we're doing nothing
public static final int STATE_CONNECTING = 2; // now initiating an outgoing connection
public static final int STATE_CONNECTED = 3; // now connected to a remote device
final ArrayList<String> devices = new ArrayList();
private final Handler mHandler;
private BluetoothAdapter mAdapter;
private BluetoothDevice device;
private ConnectThread mConnectThread;
private ConnectedThread mConnectedThread;
private BluetoothSocket socket;
private String status;
private int mState;
private boolean connectionStatus = false;
public BTHandler(Context context, Handler handler) { // Konstruktor
mAdapter = BluetoothAdapter.getDefaultAdapter();
mHandler = handler;
}
public void write(String s) {
mConnectedThread.sendRawCommand(s);
Log.v("write", "write");
}
/*
public void write(byte[] bytes) {
try {
mmOutStream.write(bytes);
} catch (IOException e) {
}
}
*/
public void connect(String deviceAddress) {
mConnectThread = new ConnectThread(deviceAddress);
mConnectThread.start();
}
private void guiHandler(int what, int arg1, String obj) {
Message msg = mHandler.obtainMessage();
msg.what = what;
msg.obj = obj;
msg.arg1 = arg1;
msg.sendToTarget();
}
private class ConnectThread extends Thread {
BluetoothSocket tmp = null;
private BluetoothSocket mmSocket;
public ConnectThread(String deviceAddress) {
mAdapter = BluetoothAdapter.getDefaultAdapter();
device = mAdapter.getRemoteDevice(deviceAddress);
BluetoothAdapter mAdapter = BluetoothAdapter.getDefaultAdapter();
BluetoothDevice device = mAdapter.getRemoteDevice(deviceAddress);
UUID uuid = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
try {
tmp = device.createRfcommSocketToServiceRecord(uuid);
//socket.connect();
//Log.v("connect", "connect");
} catch (IOException e) {
//e.printStackTrace();
//Log.v("exception", "e");
}
mmSocket = tmp;
}
public void run() {
// Cancel discovery because it will slow down the connection
mAdapter.cancelDiscovery();
byte[] buffer = new byte[1024]; // buffer store for the stream
int bytes;
try {
// Connect the device through the socket. This will block
// until it succeeds or throws an exception
mmSocket.connect();
Log.v("connect", "connect");
} catch (IOException connectException) {
// Unable to connect; close the socket and get out
try {
mmSocket.close();
Log.v("close", "close");
} catch (IOException closeException) {
}
guiHandler(Constants.TOAST, Constants.SHORT, "Connection Failed");
return;
}
guiHandler(Constants.CONNECTION_STATUS, Constants.STATE_CONNECTED, "");
mConnectedThread = new ConnectedThread(mmSocket);
mConnectedThread.start();
}
}
private class ConnectedThread extends Thread {
private final BluetoothSocket mmSocket;
private final InputStream mmInStream;
private final OutputStream mmOutStream;
private ObdMultiCommand multiCommand;
public ConnectedThread(BluetoothSocket socket) {
connectionStatus = true;
mmSocket = socket;
InputStream tmpIn = null;
OutputStream tmpOut = null;
try {
tmpIn = socket.getInputStream();
tmpOut = socket.getOutputStream();
} catch (IOException e) {
}
mmInStream = tmpIn;
mmOutStream = tmpOut;
try {
//RPMCommand engineRpmCommand = new RPMCommand();
//SpeedCommand speedCommand = new SpeedCommand();
ModuleVoltageCommand voltageCommand = new ModuleVoltageCommand();
while (!Thread.currentThread().isInterrupted()) {
//engineRpmCommand.run(mmInStream, mmOutStream); //(socket.getInputStream(), socket.getOutputStream());
//speedCommand.run(mmInStream, mmOutStream); //(socket.getInputStream(), socket.getOutputStream());
voltageCommand.run(socket.getInputStream(), socket.getOutputStream());
// TODO handle commands result
//Log.d("Log", "RPM: " + engineRpmCommand.getFormattedResult());
//Log.d("Log", "Speed: " + speedCommand.getFormattedResult());
Log.v("Log", "Voltage: " + voltageCommand.getFormattedResult());
}
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public void run() {
byte[] buffer = new byte[1024]; // buffer store for the stream
int bytes; // bytes returned from read()
OBDcmds();
// Keep listening to the InputStream until an exception occurs
while (connectionStatus) {
sendMultiCommand();
try {
Thread.sleep(500);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
// CALL this to MainActivity
public void sendRawCommand(String command) {
try {
new OdbRawCommand(command);
} catch (Exception e) {
Log.v("sendRawCommand", "e");
}
}
private void OBDcmds() { // execute commands
try {
new EchoOffCommand().run(socket.getInputStream(), socket.getOutputStream());
new LineFeedOffCommand().run(socket.getInputStream(), socket.getOutputStream());
new TimeoutCommand(100).run(socket.getInputStream(), socket.getOutputStream());
new SelectProtocolCommand(ObdProtocols.AUTO).run(socket.getInputStream(), socket.getOutputStream()); //ISO_15765_4_CAN
} catch (Exception e) {
Log.v("OBDcmds", "e");
// handle errors
}
}
/*
// 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 sendMultiCommand() {
try {
// RUN some code here
} catch (Exception e) {
}
}
}
}
SPA: One of the power platforms mentioned before.
public class SPA extends AppCompatActivity implements View.OnClickListener {
Button b2;
BTHandler btHandler;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_sp);
b2 = (Button) findViewById(R.id.getValue);
b2.setOnClickListener(this);
}
public void onClick(View v) {
int id = v.getId();
String voltage = ("AT RV");
switch (id) {
case R.id.getValue:
btHandler.write(voltage);
Log.v("Log", "getValue" + voltage);
break;
}
}
}
Logcat:

The reason of the error is here:
BTHandler btHandler;
and you are doing this:
btHandler.write(voltage);
but the object is null referenced....
you need to initialize the BTHandler in the oncreate...
or maybe better:
use a service so you can Bind all the activities to that...
PS:
Note that the BTHandler of the MainActivity is not the same as the one declared in the SPA Class... so although that btHandler is constructed and works in MainActivity doesnt mean it will work in other activities/classes

how to get filename from uri for any file selected from gallery?

I am getting null value while using context for fragment on the line
selectedPath = ImageFilePath.getPath(mContext, uri);
public class DeviceDetailFragment extends Fragment implements ConnectionInfoListener {
protected static final int CHOOSE_FILE_RESULT_CODE = 20;
private View mContentView = null;
private WifiP2pDevice device;
private WifiP2pInfo info;
ProgressDialog progressDialog = null;
private Context mContext;
public static String filename;
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
}
#Override
public void onAttach(Activity activity) {
// TODO Auto-generated method stub
super.onAttach(activity);
mContext = getActivity().getApplicationContext();
}
#SuppressLint("InflateParams")
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
mContentView = inflater.inflate(R.layout.device_detail, null);
mContentView.findViewById(R.id.btn_connect).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
WifiP2pConfig config = new WifiP2pConfig();
config.deviceAddress = device.deviceAddress;
config.wps.setup = WpsInfo.PBC;
if (progressDialog != null && progressDialog.isShowing()) {
progressDialog.dismiss();
}
progressDialog = ProgressDialog.show(getActivity(), "Press back to cancel",
"Connecting to :" + device.deviceAddress, true, true
);
((DeviceActionListener) getActivity()).connect(config);
}
});
mContentView.findViewById(R.id.btn_disconnect).setOnClickListener(
new View.OnClickListener() {
#Override
public void onClick(View v) {
((DeviceActionListener) getActivity()).disconnect();
}
});
mContentView.findViewById(R.id.btn_start_client).setOnClickListener(
new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.setType("*/*");
startActivityForResult(intent, CHOOSE_FILE_RESULT_CODE);
}
});
return mContentView;
}
#Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
Uri uri = data.getData();
if (resultCode == Activity.RESULT_OK)
{
if (requestCode == CHOOSE_FILE_RESULT_CODE)
{
String selectedPath;
selectedPath = ImageFilePath.getPath(mContext, uri);
filename = selectedPath.substring(selectedPath.lastIndexOf("/")+1);
}
}
TextView statusText = (TextView) mContentView.findViewById(R.id.status_text);
statusText.setText("Sending: " + uri);
Log.d(WiFiDirectActivity.TAG, "Intent----------- " + uri);
Intent serviceIntent = new Intent(getActivity(), FileTransferService.class);
serviceIntent.setAction(FileTransferService.ACTION_SEND_FILE);
serviceIntent.putExtra(FileTransferService.EXTRAS_FILE_PATH, uri.toString());
serviceIntent.putExtra(FileTransferService.EXTRAS_GROUP_OWNER_ADDRESS,
info.groupOwnerAddress.getHostAddress());
serviceIntent.putExtra(FileTransferService.EXTRAS_GROUP_OWNER_PORT, 8988);
getActivity().startService(serviceIntent);
}
#Override
public void onConnectionInfoAvailable(final WifiP2pInfo info) {
if (progressDialog != null && progressDialog.isShowing()) {
progressDialog.dismiss();
}
this.info = info;
this.getView().setVisibility(View.VISIBLE);
TextView view = (TextView) mContentView.findViewById(R.id.group_owner);
view.setText(getResources().getString(R.string.group_owner_text)
+ ((info.isGroupOwner == true) ? getResources().getString(R.string.yes)
: getResources().getString(R.string.no)));
view = (TextView) mContentView.findViewById(R.id.device_info);
view.setText("Group Owner IP - " + info.groupOwnerAddress.getHostAddress());
if (info.groupFormed && info.isGroupOwner) {
new FileServerAsyncTask(getActivity(), mContentView.findViewById(R.id.status_text))
.execute();
} else if (info.groupFormed) {
mContentView.findViewById(R.id.btn_start_client).setVisibility(View.VISIBLE);
((TextView) mContentView.findViewById(R.id.status_text)).setText(getResources()
.getString(R.string.client_text));
}
mContentView.findViewById(R.id.btn_connect).setVisibility(View.GONE);
}
public void showDetails(WifiP2pDevice device) {
this.device = device;
this.getView().setVisibility(View.VISIBLE);
TextView view = (TextView) mContentView.findViewById(R.id.device_address);
view.setText(device.deviceAddress);
view = (TextView) mContentView.findViewById(R.id.device_info);
view.setText(device.toString());
}
public void resetViews() {
mContentView.findViewById(R.id.btn_connect).setVisibility(View.VISIBLE);
TextView view = (TextView) mContentView.findViewById(R.id.device_address);
view.setText(R.string.empty);
view = (TextView) mContentView.findViewById(R.id.device_info);
view.setText(R.string.empty);
view = (TextView) mContentView.findViewById(R.id.group_owner);
view.setText(R.string.empty);
view = (TextView) mContentView.findViewById(R.id.status_text);
view.setText(R.string.empty);
mContentView.findViewById(R.id.btn_start_client).setVisibility(View.GONE);
this.getView().setVisibility(View.GONE);
}
public static class FileServerAsyncTask extends AsyncTask<Void, Void, String> {
private Context context;
private TextView statusText;
public FileServerAsyncTask(Context context, View statusText) {
this.context = context;
this.statusText = (TextView) statusText;
}
#Override
protected String doInBackground(Void... params) {
try {
ServerSocket serverSocket = new ServerSocket(8988);
Log.d(WiFiDirectActivity.TAG, "Server: Socket opened");
Socket client = serverSocket.accept();
Log.d(WiFiDirectActivity.TAG, "Server: connection done");
final File f = new File(Environment.getExternalStorageDirectory() + "/"
+ context.getPackageName() + "/" + filename);
File dirs = new File(f.getParent());
if (!dirs.exists())
dirs.mkdirs();
f.createNewFile();
Log.d(WiFiDirectActivity.TAG, "server: copying files " + f.toString());
InputStream inputstream = client.getInputStream();
copyFile(inputstream, new FileOutputStream(f));
serverSocket.close();
return f.getAbsolutePath();
} catch (IOException e) {
Log.e(WiFiDirectActivity.TAG, e.getMessage());
return null;
}
}
#Override
protected void onPostExecute(String result) {
if (result != null) {
statusText.setText("File copied - " + result);
Intent intent = new Intent();
intent.setAction(android.content.Intent.ACTION_VIEW);
intent.setDataAndType(Uri.parse("file://" + result), "*/*");
context.startActivity(intent);
}
}
#Override
protected void onPreExecute() {
statusText.setText("Opening a server socket");
}
}
public static boolean copyFile(InputStream inputStream, OutputStream out) {
byte buf[] = new byte[1024];
int len;
long startTime=System.currentTimeMillis();
try {
while ((len = inputStream.read(buf)) != -1) {
out.write(buf, 0, len);
}
out.close();
inputStream.close();
long endTime=System.currentTimeMillis()-startTime;
Log.v("","Time taken to transfer all bytes is : "+endTime);
} catch (IOException e) {
Log.d(WiFiDirectActivity.TAG, e.toString());
return false;
}
return true;
}
}
here is the code for the FileNamePath class
public class FileTransferService extends IntentService {
private static final int SOCKET_TIMEOUT = 5000;
public static final String ACTION_SEND_FILE = "com.example.android.wifidirect.SEND_FILE";
public static final String EXTRAS_FILE_PATH = "file_url";
public static final String EXTRAS_GROUP_OWNER_ADDRESS = "go_host";
public static final String EXTRAS_GROUP_OWNER_PORT = "go_port";
public FileTransferService(String name) {
super(name);
}
public FileTransferService() {
super("FileTransferService");
}
/*
* (non-Javadoc)
* #see android.app.IntentService#onHandleIntent(android.content.Intent)
*/
#Override
protected void onHandleIntent(Intent intent) {
Context context = getApplicationContext();
if (intent.getAction().equals(ACTION_SEND_FILE)) {
String fileUri = intent.getExtras().getString(EXTRAS_FILE_PATH);
String host = intent.getExtras().getString(EXTRAS_GROUP_OWNER_ADDRESS);
Socket socket = new Socket();
int port = intent.getExtras().getInt(EXTRAS_GROUP_OWNER_PORT);
try {
Log.d(WiFiDirectActivity.TAG, "Opening client socket - ");
socket.bind(null);
socket.connect((new InetSocketAddress(host, port)), SOCKET_TIMEOUT);
Log.d(WiFiDirectActivity.TAG, "Client socket - " + socket.isConnected());
OutputStream stream = socket.getOutputStream();
ContentResolver cr = context.getContentResolver();
InputStream is = null;
try {
is = cr.openInputStream(Uri.parse(fileUri));
} catch (FileNotFoundException e) {
Log.d(WiFiDirectActivity.TAG, e.toString());
}
DeviceDetailFragment.copyFile(is, stream);
Log.d(WiFiDirectActivity.TAG, "Client: Data written");
} catch (IOException e) {
Log.e(WiFiDirectActivity.TAG, e.getMessage());
} finally {
if (socket != null) {
if (socket.isConnected()) {
try {
socket.close();
} catch (IOException e) {
// Give up
e.printStackTrace();
}
}
}
}
}
}
}
i am not able to get the filename and only getting null.