Develop Reference

W/libEGL: EGLNativeWindowType 0x7d358f1010 disconnect failed

package com.example.yj.bluetoothapplication;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.lang.reflect.Method;
import java.util.UUID;
import android.app.Activity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.content.Intent;
import android.graphics.Color;
import android.os.Build;
import android.os.Bundle;
import android.os.Handler;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.RelativeLayout;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends Activity {
private static final String TAG = "bluetooth2";
Button btnLed1, btnLed2, btnLed3, btnpado;
TextView txtArduino;
RelativeLayout rlayout;
Handler h;
final int RECIEVE_MESSAGE = 1; // Status for Handler
private BluetoothAdapter btAdapter = null;
private BluetoothSocket btSocket = null;
private StringBuilder sb = new StringBuilder();
private static int flag = 0;
private ConnectedThread mConnectedThread;
// SPP UUID service
private static final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
// MAC-address of Bluetooth module (you must edit this line)
private static String address = "98:D3:61:FD:59:9D";
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btnLed1 = (Button) findViewById(R.id.btnLed1);
btnLed2 = (Button) findViewById(R.id.btnLed2);
btnLed3 = (Button) findViewById(R.id.btnLed3);
btnpado = (Button) findViewById(R.id.btnPado);
txtArduino = (TextView) findViewById(R.id.txtArduino);
rlayout = (RelativeLayout) findViewById(R.id.layout);
h = new Handler() {
public void handleMessage(android.os.Message msg) {
switch (msg.what) {
case RECIEVE_MESSAGE:
byte[] readBuf = (byte[]) msg.obj;
String strIncom = new String(readBuf, 0, msg.arg1);
sb.append(strIncom);
int endOfLineIndex = sb.indexOf("\r\n");
if (endOfLineIndex > 0) {
String sbprint = sb.substring(0, endOfLineIndex);
sb.delete(0, sb.length());
txtArduino.setText("Data from Arduino: " + sbprint);
if(flag%4==3){
rlayout.setBackgroundColor(Color.rgb(255, 255, 255));
}
else if(flag%4==1){
rlayout.setBackgroundColor(Color.rgb(255, 0, 0));
}
else if(flag%4==2){
rlayout.setBackgroundColor(Color.rgb(0, 255, 0));
}
else if(flag%4==0){
rlayout.setBackgroundColor(Color.rgb(0, 0, 255));
}
flag++;
btnLed1.setEnabled(true);
btnLed2.setEnabled(true);
btnLed3.setEnabled(true);
btnpado.setEnabled(true);
}
break;
}
};
};
btAdapter = BluetoothAdapter.getDefaultAdapter(); // get Bluetooth adapter
checkBTState();
btnLed1.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
mConnectedThread.write("1");
Toast.makeText(getBaseContext(), "Turn on First LED", Toast.LENGTH_SHORT).show();
}
});
btnLed2.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
mConnectedThread.write("2");
//Toast.makeText(getBaseContext(), "Turn on Second LED", Toast.LENGTH_SHORT).show();
}
});
btnLed3.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
mConnectedThread.write("3");
//Toast.makeText(getBaseContext(), "Turn on Third LED", Toast.LENGTH_SHORT).show();
}
});
btnpado.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
mConnectedThread.write("0");
//Toast.makeText(getBaseContext(), "Turn on all LEDs", Toast.LENGTH_SHORT).show();
}
});
}
private BluetoothSocket createBluetoothSocket(BluetoothDevice device) throws IOException {
if(Build.VERSION.SDK_INT >= 10){
try {
final Method m = device.getClass().getMethod("createInsecureRfcommSocketToServiceRecord", new Class[] { UUID.class });
return (BluetoothSocket) m.invoke(device, MY_UUID);
} catch (Exception e) {
Log.e(TAG, "Could not create Insecure RFComm Connection",e);
}
}
return device.createRfcommSocketToServiceRecord(MY_UUID);
}
#Override
public void onResume() {
super.onResume();
Log.d(TAG, "...onResume - try connect...");
// Set up a pointer to the remote node using it's address.
BluetoothDevice device = btAdapter.getRemoteDevice(address);
// Two things are needed to make a connection:
// A MAC address, which we got above.
// A Service ID or UUID. In this case we are using the
// UUID for SPP.
try {
btSocket = createBluetoothSocket(device);
} catch (IOException e) {
errorExit("Fatal Error", "In onResume() and socket create failed: " + e.getMessage() + ".");
}
// Discovery is resource intensive. Make sure it isn't going on
// when you attempt to connect and pass your message.
btAdapter.cancelDiscovery();
// Establish the connection. This will block until it connects.
Log.d(TAG, "...Connecting...");
try {
btSocket.connect();
Log.d(TAG, "....Connection ok...");
} catch (IOException e) {
try {
btSocket.close();
} catch (IOException e2) {
errorExit("Fatal Error", "In onResume() and unable to close socket during connection failure" + e2.getMessage() + ".");
}
}
// Create a data stream so we can talk to server.
Log.d(TAG, "...Create Socket...");
mConnectedThread = new ConnectedThread(btSocket);
mConnectedThread.start();
}
#Override
public void onPause() {
super.onPause();
Log.d(TAG, "...In onPause()...");
try {
btSocket.close();
} catch (IOException e2) {
errorExit("Fatal Error", "In onPause() and failed to close socket." + e2.getMessage() + ".");
}
}
private void checkBTState() {
// Check for Bluetooth support and then check to make sure it is turned on
// Emulator doesn't support Bluetooth and will return null
if(btAdapter==null) {
errorExit("Fatal Error", "Bluetooth not support");
} else {
if (btAdapter.isEnabled()) {
Log.d(TAG, "...Bluetooth ON...");
} else {
//Prompt user to turn on Bluetooth
Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBtIntent, 1);
}
}
}
private void errorExit(String title, String message){
Toast.makeText(getBaseContext(), title + " - " + message, Toast.LENGTH_LONG).show();
finish();
}
private class ConnectedThread extends Thread {
private final InputStream mmInStream;
private final OutputStream mmOutStream;
public ConnectedThread(BluetoothSocket socket) {
InputStream tmpIn = null;
OutputStream tmpOut = null;
// Get the input and output streams, using temp objects because
// member streams are final
try {
tmpIn = socket.getInputStream();
tmpOut = socket.getOutputStream();
} catch (IOException e) { }
mmInStream = tmpIn;
mmOutStream = tmpOut;
}
public void run() {
byte[] buffer = new byte[256]; // buffer store for the stream
int bytes; // bytes returned from read()
// Keep listening to the InputStream until an exception occurs
while (true) {
try {
// Read from the InputStream
bytes = mmInStream.read(buffer); // Get number of bytes and message in "buffer"
h.obtainMessage(RECIEVE_MESSAGE, bytes, -1, buffer).sendToTarget(); // Send to message queue Handler
} catch (IOException e) {
break;
}
}
}
/* Call this from the main activity to send data to the remote device */
public void write(String message) {
Log.d(TAG, "...Data to send: " + message + "...");
byte[] msgBuffer = message.getBytes();
try {
mmOutStream.write(msgBuffer);
} catch (IOException e) {
Log.d(TAG, "...Error data send: " + e.getMessage() + "...");
}
}
}
D/BluetoothSocket: close() this: android.bluetooth.BluetoothSocket#d1bd8ab, channel: 1, mSocketIS: android.net.LocalSocketImpl$SocketInputStream#218b08, mSocketOS: android.net.LocalSocketImpl$SocketOutputStream#6d4d2a1mSocket: android.net.LocalSocket#a50ecc6 impl:android.net.LocalSocketImpl#3bd5487 fd:java.io.FileDescriptor#ec84fb4, mSocketState: CONNECTED D/ViewRootImpl#3a2e96b[MainActivity]: MSG_WINDOW_FOCUS_CHANGED 0 1 D/InputMethodManager: prepareNavigationBarInfo() DecorView#a62bffa[MainActivity] getNavigationBarColor() -855310 D/InputTransport: Input channel destroyed: fd=76 W/libEGL: EGLNativeWindowType 0x7d358f2010 disconnect failed D/OpenGLRenderer: eglDestroySurface = 0x7d1f6ac180, 0x7d358f2000 D/ViewRootImpl#3a2e96b[MainActivity]: Relayout returned: old=[0,0][1080,2280] new=[0,0][1080,2280] result=0x5 surface={valid=false 0} changed=true D/ViewRootImpl#3a2e96b[MainActivity]: setWindowStopped(true) old=false D/ViewRootImpl#3a2e96b[MainActivity]: Surface release. android.view.WindowManagerGlobal.setStoppedState:669 android.app.Activity.performStop:7647 android.app.ActivityThread.callActivityOnStop:4378 android.app.ActivityThread.performStopActivityInner:4356 android.app.ActivityThread.handleStopActivity:4431 android.app.servertransaction.StopActivityItem.execute:41 android.app.servertransaction.TransactionExecutor.executeLifecycleState:145 android.app.servertransaction.TransactionExecutor.execute:70 D/BluetoothSocket: close() this: android.bluetooth.BluetoothSocket#f21e178, channel: 1, mSocketIS: android.net.LocalSocketImpl$SocketInputStream#eefc051, mSocketOS: android.net.LocalSocketImpl$SocketOutputStream#853c0b6mSocket: null, mSocketState: CLOSED Process 30538 terminated.

Manage Bluetooth Communication

Im actually trying to interact with a bluetooth module controlled by a microcontroller PIC.
So i need to build an android app in order to send caracters by bluetooth.
But im kind of lost.
The beginning is quiet clear to me ( enabling bluetooth and connect as client)
But i dont know how to interact with my Bluetooth Service class from my MainActivity.
How to interact with write and read.
I can see that im successfully Connected to my device.
ALEA is the name of the BT module i want to connect to.
Thanks for your help
package com.example.stef.bluetoothencore;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.content.Intent;
import android.os.Handler;
import android.os.Message;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.CheckBox;
import android.widget.ListView;
import android.widget.Toast;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.Set;
import java.util.UUID;
public class MainActivity extends AppCompatActivity {
private BluetoothAdapter mBluetoothAdapter;
ArrayList<BluetoothDevice> arrayListBluetoothDevices = null;
ArrayList<String> NomBT=null;
BluetoothDevice mydevice;
int position_alea=0;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ListView lv=(ListView)findViewById(R.id.listdevice);
CheckBox Aleabox=(CheckBox) findViewById(R.id.checkAlea);
arrayListBluetoothDevices = new ArrayList<BluetoothDevice>();
NomBT= new ArrayList<String>();
mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (mBluetoothAdapter == null) {
// Device does not support Bluetooth
}
if (!mBluetoothAdapter.isEnabled()) {
Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBtIntent, 1);
}
Set<BluetoothDevice> pairedDevices = mBluetoothAdapter.getBondedDevices();
if (pairedDevices.size() > 0) {
for (BluetoothDevice device : pairedDevices) {
BluetoothDevice mDevice = device;
arrayListBluetoothDevices.add(device); // On charge la liste de Device
NomBT.add(device.getName().toString());
if(device.getName().toString().equals("ALEA")){
mydevice=device;
Aleabox.setChecked(true);
Aleabox.setText(mydevice.getName().toString());
}
}
}
final ArrayAdapter adapter = new ArrayAdapter(this, android.R.layout.simple_list_item_1, NomBT);
lv.setAdapter(adapter);
lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
// position_alea=i;
//Toast.makeText(getApplicationContext(), mydevice.getName().toString(), Toast.LENGTH_SHORT).show();
ConnectThread mConnectThread = new ConnectThread(mydevice);
mConnectThread.start();
}
});
}
private class ConnectThread extends Thread {
private final BluetoothSocket mmSocket;
private final BluetoothDevice mmDevice;
private final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
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;
}
ConnectedThread mConnectedThread = new ConnectedThread(mmSocket);
mConnectedThread.start();
mConnectedThread.write("c".getBytes());
}
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;
try {
tmpIn = socket.getInputStream();
tmpOut = socket.getOutputStream();
} catch (IOException e) { }
mmInStream = tmpIn;
mmOutStream = tmpOut;
}
public void run() {
byte[] buffer = new byte[1024];
int begin = 0;
int bytes = 0;
while (true) {
try {
bytes += mmInStream.read(buffer, bytes, buffer.length - bytes);
for(int i = begin; i < bytes; i++) {
if(buffer[i] == "#".getBytes()[0]) {
mHandler.obtainMessage(1, begin, i, buffer).sendToTarget();
begin = i + 1;
if(i == bytes - 1) {
bytes = 0;
begin = 0;
}
}
}
} catch (IOException e) {
break;
}
}
}
public void write(byte[] bytes) {
try {
mmOutStream.write(bytes);
} catch (IOException e) { }
}
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) { }
}
}
Handler mHandler = new Handler() {
#Override
public void handleMessage(Message msg) {
byte[] writeBuf = (byte[]) msg.obj;
int begin = (int)msg.arg1;
int end = (int)msg.arg2;
switch(msg.what) {
case 1:
String writeMessage = new String(writeBuf);
writeMessage = writeMessage.substring(begin, end);
break;
}
}
};
}

Up, im still blocked, i am connected to my device but i can't read or write data ...

I can't send the data through Bluetooth

I wrote the application in Android Studio which has to send 1 on Arduino Pro Mini. Data is sent but doesn't reach Arduino. I checked Arduino through Bluetooth Terminal and everything was OK so the problem is in code. What is wrong?
package com.example.niko.motoco;
import android.app.Activity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.content.Intent;
import android.os.Bundle;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.util.Log;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
import java.io.IOException;
import java.io.OutputStream;
import java.util.UUID;
public class MainActivity extends AppCompatActivity {
BluetoothAdapter btAdapter = null ;
BluetoothDevice btDevice = null;
BluetoothSocket btSocket = null;
final String LOG_TAG = "myLogs";
Button btConnect, btSend;
public TextView checkText;
private static final int REQUEST_ENABLE_BT = 1;
private static final int CONNECTEDdevice = 2;
Boolean connection = false;
private static String MAC = null;
UUID my_UUID = UUID.fromString("00001101-0000-1000-8000-00805f9b34fb");
private ConnectedThread MyThread = null;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
checkText = (TextView) findViewById(R.id.checkText);
btConnect = (Button)findViewById(R.id.btConnect);
btSend = (Button)findViewById(R.id.btSend);
btAdapter = BluetoothAdapter.getDefaultAdapter();
if (btAdapter == null) {
Toast.makeText(getApplicationContext(),"Device does not support Bluetooth",Toast.LENGTH_LONG).show();
} else if (!btAdapter.isEnabled()) {
Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
}
btConnect.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
if (connection) {
// disconnect
try {
btSocket.close();
connection = false;
btConnect.setText("Connect");
Toast.makeText(getApplicationContext(),"Bluetooht is disconnected:",Toast.LENGTH_LONG).show();
} catch (IOException error) {
Toast.makeText(getApplicationContext(),"Error;" + error,Toast.LENGTH_LONG).show();
}
} else {
// connect
Intent ListDevices = new Intent(MainActivity.this, ListDevices.class);
startActivityForResult(ListDevices,CONNECTEDdevice);
}
}
});
btSend.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
MyThread.write((byte) 1);
Toast.makeText(getApplicationContext(),"Sending 1",Toast.LENGTH_LONG).show();
}
});
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
//super.onActivityResult(requestCode, resultCode, data);
switch (requestCode) {
case REQUEST_ENABLE_BT:
if(resultCode == Activity.RESULT_OK) {
Toast.makeText(getApplicationContext(),"bluetooth is activated",Toast.LENGTH_LONG).show();
} else {
Toast.makeText(getApplicationContext(),"bluetooth is not activated",Toast.LENGTH_LONG).show();
finish();
}
break;
case CONNECTEDdevice :
if (resultCode == Activity.RESULT_OK) {
MAC = data.getExtras().getString(ListDevices.MACaddress);
btDevice = btAdapter.getRemoteDevice(MAC);
try {
btSocket = btDevice.createRfcommSocketToServiceRecord(my_UUID);
btSocket.connect();
connection = true;
btConnect.setText("Disconnect");
Toast.makeText(getApplicationContext(),"MAC of connected device:" + MAC,Toast.LENGTH_LONG).show();
MyThread = new ConnectedThread(btSocket);
//MyThread.start();
} catch (IOException error) {
connection = false;
Toast.makeText(getApplicationContext(),"Error:" + error,Toast.LENGTH_LONG).show();
}
}else {
Toast.makeText(getApplicationContext(),"didn't get MAC",Toast.LENGTH_LONG).show();
}
}
}
private class ConnectedThread extends Thread {
private final BluetoothSocket btSocket2;
private final OutputStream OutStream;
public ConnectedThread(BluetoothSocket socket) {
btSocket2 = socket;
OutputStream tmpOut = null;
try {
tmpOut = socket.getOutputStream();
} catch (IOException e) { }
OutStream = tmpOut;
}
public void write(byte bytes) {
try {
OutStream.write(bytes);
} catch (IOException e) { }
}
public void cancel() {
try {
btSocket2.close();
} catch (IOException e) { }
}
}
}

What's wrong ? At least those 2 pieces of code are wrong :
try {
tmpOut = socket.getOutputStream();
} catch (IOException e) { }
And later:
try {
OutStream.write(bytes);
} catch (IOException e) { }
When something goes wrong you catch the exception silently and loose all chances to identify the root cause.
Change the code to something like this :
try {
tmpOut = socket.getOutputStream();
} catch (IOException e) {
Log.(TAG, "Fail to get socket output stream" ,e);
}
And later :
try {
OutStream.write(bytes);
} catch (IOException e) {
Log.(TAG, "Fail to write on socket output stream" ,e);
}
Then re-run your code and look at the logcat. You will probably see the cause of your problems.

What can I do by getBluetoothService() called with no BluetoothManagerCallback ?

hi I want to write a Android java application that can connect with a bluetooth device but I get the error:
W/BluetoothAdapter﹕ getBluetoothService() called with no BluetoothManagerCallback
I use a Nexus 5 device with android version 4.4.4
here is my code:
package com.example.tarasov.bluetoothexample;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.Set;
import java.util.UUID;
import android.view.Menu;
import android.view.MenuItem;
import android.app.Activity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.Toast;
public class MyActivity extends Activity implements OnItemClickListener {
/*
* Deklaration
* */
ArrayAdapter<String> listAdapter;
ListView listView;
BluetoothAdapter btAdapter;
Set<BluetoothDevice> deviceArray;
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) {
// TODO Auto-generated method stub
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(), "CONNECT", Toast.LENGTH_SHORT).show();
String s = "successfully connected";
connectedThread.write(s.getBytes());
Log.i(tag, "connected");
break;
case MESSAGE_READ:
byte[] readBuf = (byte[])msg.obj;
String string = new String(readBuf);
Toast.makeText(getApplicationContext(), string, Toast.LENGTH_SHORT).show();
break;
}
}
};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_my);
init(); //Initialisierung der Komponenten
if(btAdapter==null)
{
Toast.makeText(getApplicationContext(), "Kein Bluetooth aktiviert", Toast.LENGTH_SHORT).show();
finish();
}
else
{
if (!btAdapter.isEnabled()){
turnOnBT();
}
getPairedDevices();
startDiscovery();
}
}
private void startDiscovery() {
btAdapter.cancelDiscovery();
btAdapter.startDiscovery();
}
private void turnOnBT() {
Intent intent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(intent,1);
}
private void getPairedDevices() {
deviceArray = btAdapter.getBondedDevices();
if (deviceArray.size()>0){
for (BluetoothDevice device:deviceArray){
pairedDevices.add(device.getName());
}
}
}
private void init(){
listView = (ListView)findViewById(R.id.listView); //bindet ListView
listView.setOnItemClickListener(this);
listAdapter = new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1,0);
listView.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) {
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))){
s = "(Verbunden)";
break;
}
}
listAdapter.add(device.getName()+" "+s+" "+"\n"+device.getAddress());
}
else if (BluetoothAdapter.ACTION_DISCOVERY_STARTED.equals(action)){
}
else if (BluetoothAdapter.ACTION_DISCOVERY_FINISHED.equals(action)){
}
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 onPause() {
super.onPause();
unregisterReceiver(receiver);
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode==RESULT_CANCELED){
Toast.makeText(getApplicationContext(), "Bluetooth muss erst aktiviert werden", Toast.LENGTH_SHORT).show();
finish();
}
}
#Override
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3) {
if (btAdapter.isDiscovering()){
btAdapter.cancelDiscovery();
}
if (listAdapter.getItem(arg2).contains("Verbunden")){
BluetoothDevice selectedDevice = devices.get(arg2);
ConnectThread connect = new ConnectThread(selectedDevice);
connect.start();
Log.i(tag, "in click listener");
}
else
{
Toast.makeText(getApplicationContext(), "Gerät ist nicht verbunden", Toast.LENGTH_SHORT).show();
}
}
/*
* Hilfsklassen
* */
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;
Log.i(tag, "construct");
// 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) {
Log.i(tag, "get socket failed");
}
mmSocket = tmp;
}
public void run() {
// Cancel discovery because it will slow down the connection
btAdapter.cancelDiscovery();
Log.i(tag, "connect - run");
try {
// Connect the device through the socket. This will block
// until it succeeds or throws an exception
mmSocket.connect();
Log.i(tag, "connect - succeeded");
} catch (IOException connectException) { Log.i(tag, "connect failed");
// 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)
mHandler.obtainMessage(SUCCESS_CONNECT, mmSocket).sendToTarget();
}
/** 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) { }
}
}

Android NIO Server Selectors Reading When no message is sent

I'm trying to use a NIO server to read/write to a client for TCP connections. I've made a successful connection, and my initial message is sent to the server and correctly processed. It says that the server is sending a message back, but I'm not receiving any input on the client side. Also, after the server sends a message back, the application crashes saying that it was trying to read a null pointer (Line 127 server code).
It's important to note that I'm new to this concept and I don't really understand selectors. I've looked at tutorials, but contradictary messages have led me to be even more confused on the issue. If anyone has any good tutorials on this topic I'd be greatly appreciative.
Here's my code.
Client Main Activity Screen
package com.example.client;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.Intent;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import com.example.client.ServerService.Connect;
public class MainActivity extends Activity {
Button button;
TextView textView;
EditText editText;
EditText editTextps;
static Handler handler;
Connect connect=null;
Object myLock=new Object();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
button=(Button) findViewById(R.id.button1);
textView=(TextView) findViewById(R.id.textView1);
editText=(EditText) findViewById(R.id.editText1);
editTextps=(EditText) findViewById(R.id.editText2);
handler=new Handler(){
#Override
public void handleMessage(Message msg) { //Handle code for receiving messages
super.handleMessage(msg);//when a message is received it's input is processed here
Bundle bundle=msg.getData();
if(bundle.getInt("int") == 2){
if(bundle.getInt("valid") == 1){
Intent i = new Intent();
i.setClassName("com.example.client",
"com.example.client.ReadyScreen");
startActivity(i);
}else{
alertMessage();
editText.setText("");
editTextps.setText("");
}
}
}
};
startService(new Intent(getBaseContext(), ServerService.class));
button.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View arg0) {
String str=editText.getText().toString();
String strps=editTextps.getText().toString();
Message msg=Message.obtain();
Bundle bundle=new Bundle();
bundle.putString("name", str);
bundle.putString("password", strps);
msg.setData(bundle);
ServerService.threadHandler.sendMessage(msg);
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
public void alertMessage() {
final android.app.AlertDialog.Builder show = new AlertDialog.Builder(this).setTitle("Error").setMessage("Wrong username/password").setNeutralButton("close", null);
show.show();
}
}
Server Service where I'm running the connection and IO
package com.example.client;
import java.net.InetSocketAddress;
import java.net.SocketAddress;
import java.nio.ByteBuffer;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.SocketChannel;
import android.app.Service;
import android.content.Intent;
import android.os.Handler;
import android.os.IBinder;
import android.os.Looper;
import android.os.Message;
import android.util.Log;
import android.widget.Toast;
public class ServerService extends Service {
Handler handler;
static MyHandle threadHandler;
Connect connect=null;
Object myLock=new Object();
static SocketChannel socketChannel=null;
public ByteBuffer sendBuffer=ByteBuffer.allocate(1024);
static ByteBuffer receiveBuffer=ByteBuffer.allocate(1024);
static Selector selector;
private static final String TAG = ServerService.class.getSimpleName();
#Override
public IBinder onBind(Intent intent) {
return null;
}
#Override
public int onStartCommand(Intent intent, int flags, int startId){
Log.d(TAG, "Started running the service");
System.out.println(TAG + "Started running the service");
(new Thread(new ReceivingThread())).start();
(new Thread(new SendingThread())).start();
return START_STICKY;
}
#Override
public void onDestroy(){
super.onDestroy();
Toast.makeText(this, "Service Stopped", Toast.LENGTH_LONG).show();
}
class Connect {
SocketChannel socketChannel=null;
public ByteBuffer sendBuffer=ByteBuffer.allocate(1024);
ByteBuffer receiveBuffer=ByteBuffer.allocate(1024);
Selector selector;
public Connect() {
try {
socketChannel=SocketChannel.open();
SocketAddress remoteAddress=new InetSocketAddress("192.168.2.17", 20001);
socketChannel.connect(remoteAddress);
socketChannel.configureBlocking(false);
selector=Selector.open();
socketChannel.register(selector, SelectionKey.OP_READ);
} catch (Exception e) {
e.printStackTrace();
}
}
}
public class ReceivingThread implements Runnable{
#Override
public void run() {
Log.d(TAG, "Started running the receive thread");
connect=new Connect();
try {
while(true){
if(connect.selector.select()==0)
continue;
Play receivedMessage = new Play();
receivedMessage.play();
}
} catch (Exception e) {
e.printStackTrace();
System.out.println(e.getMessage());
}
}
}
public class SendingThread implements Runnable{
#Override
public void run() {
Log.d(TAG, "Started running the send thread");
Looper.prepare();
threadHandler=new MyHandle(Looper.myLooper());
Looper.loop();
}
}
class MyHandle extends Handler{
public MyHandle(){
}
public MyHandle(Looper looper){
super(looper);
}
public void handleMessage(Message msg){
String str=msg.getData().getString("name");
String strps=msg.getData().getString("password");
MyMessage message=new MyMessage();
message.setb((byte)1);
message.setUsername(str);
message.setPassword(strps);
try {
connect.sendBuffer.clear();
connect.sendBuffer.put(message.Message2Byte());
connect.sendBuffer.flip();
connect.socketChannel.write(connect.sendBuffer);
} catch (Exception e) {
e.printStackTrace();
}
}
}
}
The Server Code
package mytcp;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.nio.ByteBuffer;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.ServerSocketChannel;
import java.nio.channels.SocketChannel;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import java.util.Timer;
import java.util.TimerTask;
public class NioServer {
/**
* #param args
*/
private int port = 20001;
final makeFlagFalse timerFlag = new makeFlagFalse();
static makeFlagFalse loginLoopBoolean = new makeFlagFalse();
private static ByteBuffer sBuffer = ByteBuffer.allocate(1024);
private static ByteBuffer rBuffer = ByteBuffer.allocate(1024);
private static Map<SocketChannel, Integer> clientsMap = new HashMap<SocketChannel, Integer>();
private Selector selector = null;
private ServerSocketChannel serverSocketChannel = null;
private Object gate = new Object();
public NioServer(int port) {
this.port = port;
try {
init();
} catch (Exception e) {
e.printStackTrace();
}
}
public static void main(String[] args) throws InterruptedException, IOException {
final NioServer server = new NioServer(20001);
Thread accept = new Thread() {
public void run() {
server.accept();
}
};
accept.start();
while (loginLoopBoolean.flag == true)
server.loginService();
server.gamePlay(clientsMap);
}
public void init() throws IOException {
selector = Selector.open();
serverSocketChannel = ServerSocketChannel.open();
serverSocketChannel.socket().setReuseAddress(true);
// serverSocketChannel.configureBlocking(false);
serverSocketChannel.socket().bind(new InetSocketAddress(port));
System.out.println("服务器启动");
}
public void accept() {
while (true) {
try {
SocketChannel socketChannel = serverSocketChannel.accept();
System.out.println("receive the connection from "
+ socketChannel.socket().getInetAddress() + ":"
+ socketChannel.socket().getPort());
socketChannel.configureBlocking(false);
synchronized (gate) {
selector.wakeup();
socketChannel.register(selector, SelectionKey.OP_READ);
}
} catch (Exception e) {
e.printStackTrace();
System.out.println(e.getMessage());
System.out.println("Damn it");
}
}
}
public void loginService() throws InterruptedException {
synchronized (gate) {
}
try {
int n = selector.select();
if (n == 0){}
else{
Set<SelectionKey> selectionKeys = selector.selectedKeys();
for (SelectionKey key : selectionKeys) {
try {
if (key.isReadable()) {
handle_receive_login(key);
}
} catch (Exception e) {
try {
if (key != null) {
key.cancel();
key.channel().close();
}
} catch (Exception ex) {
e.printStackTrace();
}
}
}
selectionKeys.clear();
}
} catch (Exception e) {
e.printStackTrace();
}
}
public void handle_receive_login(SelectionKey key) {
SocketChannel socketChannel = null;
ServerMessage message = null;
ServerMessage sendMessage = new ServerMessage();
socketChannel = (SocketChannel) key.channel();
rBuffer.clear();
try {
int count = socketChannel.read(rBuffer);
if (count > 0) {
rBuffer.flip();
message = ServerMessage.byte2Message(rBuffer.array());
System.out.println("Receive from"+ socketChannel.socket().getInetAddress() + " : "+ message.getb());
switch(message.getb()){
case(1):
int valid = DB.idCheck(message.getUsername(),
message.getPassword());
sendMessage.setb((byte) 2);
sendMessage.setValid(valid);
sendMes sendMes = new sendMes(sendMessage, socketChannel);
sendMes.send();
break;
case(2):
break;
case (3):
if(timerFlag.flag){
if(message.getReady() == 1){
if(clientsMap.size() < 6){
clientsMap.put(socketChannel, clientsMap.size() + 1);
sendMessage.setb((byte) 3);
sendMessage.setReady(1);
sendMes sendMes1 = new sendMes(sendMessage, socketChannel);
sendMes1.send();
}
else{
sendMessage.setb((byte) 3);
sendMessage.setReady(0);
sendMes sendMes1 = new sendMes(sendMessage, socketChannel);
sendMes1.send();
}
Timer timer = new Timer();
System.out.println("flag is " + timerFlag.flag);
TimerTask task = new TimerTask(){
public void run(){
timerFlag.falsify();
System.out.println("flag now is " + timerFlag.flag);
}
};
timer.schedule(task, 20*1000);
}
}else{
sendMessage.setb((byte) -1); /*-1 implies that game is currently in progress*/
sendMes sendMes1 = new sendMes(sendMessage, socketChannel);
sendMes1.send();
}
break;
case (4):
if(timerFlag.flag == true){
sendMessage.setb((byte) -2); /*send message saying "waiting for other players*/
sendMes sendMes1 = new sendMes(sendMessage, socketChannel);
sendMes1.send();
}else{
loginLoopBoolean.falsify();
}
break;
}
}/*end of if(count=0)*/
} catch (Exception e) {
e.printStackTrace();
key.cancel();
try {
socketChannel.close();
} catch (Exception ex) {
ex.printStackTrace();
}
}
}
public void gamePlay(Map<SocketChannel, Integer> clientsMap) throws IOException, InterruptedException{
Dealer dealer = new Dealer();
dealer.createDeck();
ServerMessage sendMessage = new ServerMessage();
if(!clientsMap.isEmpty()){
Set<SocketChannel> clientSet = clientsMap.keySet();
Iterator<SocketChannel> iterator=clientSet.iterator();
SocketChannel currentPlayer;
while(iterator.hasNext()){
currentPlayer=iterator.next();
sendMessage.setb((byte) 4);
sendMessage.setCard1(dealer.dealCard(dealer.deck));
sendMessage.setCard2(dealer.dealCard(dealer.deck));
sendMes sendMes1 = new sendMes(sendMessage, currentPlayer);
sendMes1.send();
}
//send who's turn it is
loginService();
}
}
public static class makeFlagFalse{
boolean flag;
public makeFlagFalse() {
this.flag = true;
}
public void falsify(){
flag = false;
}
public void makeTrue(){
flag = true;
}
}
public class sendMes{
ServerMessage message;
SocketChannel currentPlayer;
sendMes(ServerMessage message,SocketChannel currentPlayer){
this.message = message;
this.currentPlayer=currentPlayer;
}
public void send() throws IOException{
sBuffer.clear();
sBuffer.put(message.Message2Byte());
sBuffer.flip();
currentPlayer.write(sBuffer);
}
}
}
I'm appreciative of any kind of help.
Thank you

private Object gate = new Object();
it should be volatile