I want to send a simple string data such as 'a' from an android device to other one via bluetooth. I looked sample bluetooth code in android sdk but it is so complex for me. I cannot understand how I can send only specific data when I press a button. How can I solve this problem?
private OutputStream outputStream;
private InputStream inStream;
private void init() throws IOException {
BluetoothAdapter blueAdapter = BluetoothAdapter.getDefaultAdapter();
if (blueAdapter != null) {
if (blueAdapter.isEnabled()) {
Set<BluetoothDevice> bondedDevices = blueAdapter.getBondedDevices();
if(bondedDevices.size() > 0) {
Object[] devices = (Object []) bondedDevices.toArray();
BluetoothDevice device = (BluetoothDevice) devices[position];
ParcelUuid[] uuids = device.getUuids();
BluetoothSocket socket = device.createRfcommSocketToServiceRecord(uuids[0].getUuid());
socket.connect();
outputStream = socket.getOutputStream();
inStream = socket.getInputStream();
}
Log.e("error", "No appropriate paired devices.");
} else {
Log.e("error", "Bluetooth is disabled.");
}
}
}
public void write(String s) throws IOException {
outputStream.write(s.getBytes());
}
public void run() {
final int BUFFER_SIZE = 1024;
byte[] buffer = new byte[BUFFER_SIZE];
int bytes = 0;
int b = BUFFER_SIZE;
while (true) {
try {
bytes = inStream.read(buffer, bytes, BUFFER_SIZE - bytes);
} catch (IOException e) {
e.printStackTrace();
}
}
}
I made the following code so that even beginners can understand. Just copy the code and read comments. Note that message to be send is declared as a global variable which you can change just before sending the message. General changes can be done in Handler function.
multiplayerConnect.java
import android.annotation.SuppressLint;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothServerSocket;
import android.bluetooth.BluetoothSocket;
import android.content.Intent;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
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 multiplayerConnect extends AppCompatActivity {
public static final int REQUEST_ENABLE_BT=1;
ListView lv_paired_devices;
Set<BluetoothDevice> set_pairedDevices;
ArrayAdapter adapter_paired_devices;
BluetoothAdapter bluetoothAdapter;
public static final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
public static final int MESSAGE_READ=0;
public static final int MESSAGE_WRITE=1;
public static final int CONNECTING=2;
public static final int CONNECTED=3;
public static final int NO_SOCKET_FOUND=4;
String bluetooth_message="00";
#SuppressLint("HandlerLeak")
Handler mHandler=new Handler()
{
#Override
public void handleMessage(Message msg_type) {
super.handleMessage(msg_type);
switch (msg_type.what){
case MESSAGE_READ:
byte[] readbuf=(byte[])msg_type.obj;
String string_recieved=new String(readbuf);
//do some task based on recieved string
break;
case MESSAGE_WRITE:
if(msg_type.obj!=null){
ConnectedThread connectedThread=new ConnectedThread((BluetoothSocket)msg_type.obj);
connectedThread.write(bluetooth_message.getBytes());
}
break;
case CONNECTED:
Toast.makeText(getApplicationContext(),"Connected",Toast.LENGTH_SHORT).show();
break;
case CONNECTING:
Toast.makeText(getApplicationContext(),"Connecting...",Toast.LENGTH_SHORT).show();
break;
case NO_SOCKET_FOUND:
Toast.makeText(getApplicationContext(),"No socket found",Toast.LENGTH_SHORT).show();
break;
}
}
};
#Override
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.multiplayer_bluetooth);
initialize_layout();
initialize_bluetooth();
start_accepting_connection();
initialize_clicks();
}
public void start_accepting_connection()
{
//call this on button click as suited by you
AcceptThread acceptThread = new AcceptThread();
acceptThread.start();
Toast.makeText(getApplicationContext(),"accepting",Toast.LENGTH_SHORT).show();
}
public void initialize_clicks()
{
lv_paired_devices.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id)
{
Object[] objects = set_pairedDevices.toArray();
BluetoothDevice device = (BluetoothDevice) objects[position];
ConnectThread connectThread = new ConnectThread(device);
connectThread.start();
Toast.makeText(getApplicationContext(),"device choosen "+device.getName(),Toast.LENGTH_SHORT).show();
}
});
}
public void initialize_layout()
{
lv_paired_devices = (ListView)findViewById(R.id.lv_paired_devices);
adapter_paired_devices = new ArrayAdapter(getApplicationContext(),R.layout.support_simple_spinner_dropdown_item);
lv_paired_devices.setAdapter(adapter_paired_devices);
}
public void initialize_bluetooth()
{
bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (bluetoothAdapter == null) {
// Device doesn't support Bluetooth
Toast.makeText(getApplicationContext(),"Your Device doesn't support bluetooth. you can play as Single player",Toast.LENGTH_SHORT).show();
finish();
}
//Add these permisions before
// <uses-permission android:name="android.permission.BLUETOOTH" />
// <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
// <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
// <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
if (!bluetoothAdapter.isEnabled()) {
Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
}
else {
set_pairedDevices = bluetoothAdapter.getBondedDevices();
if (set_pairedDevices.size() > 0) {
for (BluetoothDevice device : set_pairedDevices) {
String deviceName = device.getName();
String deviceHardwareAddress = device.getAddress(); // MAC address
adapter_paired_devices.add(device.getName() + "\n" + device.getAddress());
}
}
}
}
public class AcceptThread extends Thread
{
private final BluetoothServerSocket serverSocket;
public AcceptThread() {
BluetoothServerSocket tmp = null;
try {
// MY_UUID is the app's UUID string, also used by the client code
tmp = bluetoothAdapter.listenUsingRfcommWithServiceRecord("NAME",MY_UUID);
} catch (IOException e) { }
serverSocket = tmp;
}
public void run() {
BluetoothSocket socket = null;
// Keep listening until exception occurs or a socket is returned
while (true) {
try {
socket = serverSocket.accept();
} catch (IOException e) {
break;
}
// If a connection was accepted
if (socket != null)
{
// Do work to manage the connection (in a separate thread)
mHandler.obtainMessage(CONNECTED).sendToTarget();
}
}
}
}
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
bluetoothAdapter.cancelDiscovery();
try {
// Connect the device through the socket. This will block
// until it succeeds or throws an exception
mHandler.obtainMessage(CONNECTING).sendToTarget();
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)
// bluetooth_message = "Initial message"
// mHandler.obtainMessage(MESSAGE_WRITE,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 = new byte[2]; // 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);
// 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) { }
}
}
}
multiplayer_bluetooth.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Challenge player"/>
<ListView
android:id="#+id/lv_paired_devices"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="1">
</ListView>
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Make sure Device is paired"/>
</LinearLayout>
Related
I am trying to send String message via Bluetooh. I am using code from this post:send message
I would like to send message on OnClick() to another connected device. Currently i can display paired devices and i am able to connect with them.
P.S I am trying to send message in write() function. When i tried to debug the code, i've figured out that debugger don't enter toMESSAGE WRITE on MESSAGE READ statement. Thanks for any help.
public class BluetoothActivity extends AppCompatActivity {
public static final int REQUEST_ENABLE_BT=1;
ListView lv_paired_devices;
Button sendMessage;
Set<BluetoothDevice> set_pairedDevices;
ArrayAdapter adapter_paired_devices;
BluetoothAdapter bluetoothAdapter;
public static final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
public static final int MESSAGE_READ=0;
public static final int MESSAGE_WRITE=1;
public static final int CONNECTING=2;
public static final int CONNECTED=3;
public static final int NO_SOCKET_FOUND=4;
String bluetooth_message="00";
#SuppressLint("HandlerLeak")
Handler mHandler=new Handler()
{
#Override
public void handleMessage(Message msg_type) {
super.handleMessage(msg_type);
switch (msg_type.what){
case MESSAGE_READ:
byte[] readbuf=(byte[])msg_type.obj;
String string_recieved=new String(readbuf);
Log.i("TAGREAD", "Bluetooth not supported");
Toast.makeText(getApplicationContext(),string_recieved,Toast.LENGTH_LONG).show();
//do some task based on recieved string
break;
case MESSAGE_WRITE:
if(msg_type.obj!=null){
ConnectedThread connectedThread=new ConnectedThread((BluetoothSocket)msg_type.obj);
connectedThread.write(bluetooth_message.getBytes());
Log.i("TAGWRITE", "Bluetooth not supported");
}
break;
case CONNECTED:
Toast.makeText(getApplicationContext(),"Connected",Toast.LENGTH_SHORT).show();
break;
case CONNECTING:
Toast.makeText(getApplicationContext(),"Connecting...",Toast.LENGTH_SHORT).show();
break;
case NO_SOCKET_FOUND:
Toast.makeText(getApplicationContext(),"No socket found",Toast.LENGTH_SHORT).show();
break;
}
}
};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getSupportActionBar().setTitle("Sparowane urządzenia");
bluetoothAdapter=BluetoothAdapter.getDefaultAdapter();
if (bluetoothAdapter == null) {
Log.i("TAGTAG", "Bluetooth not supported");
// Show proper message here
finish();
}
else{
setContentView(R.layout.activity_bluetooth);
initialize_layout();
initialize_bluetooth();
start_accepting_connection();
initialize_clicks();
}
}
public void start_accepting_connection()
{
//call this on button click as suited by you
AcceptThread acceptThread = new AcceptThread();
acceptThread.start();
Toast.makeText(getApplicationContext(),"accepting",Toast.LENGTH_SHORT).show();
}
public void initialize_clicks()
{
lv_paired_devices.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id)
{
Object[] objects = set_pairedDevices.toArray();
BluetoothDevice device = (BluetoothDevice) objects[position];
ConnectThread connectThread = new ConnectThread(device);
connectThread.start();
Toast.makeText(getApplicationContext(),"device choosen "+device.getName(),Toast.LENGTH_SHORT).show();
}
});
}
public void initialize_layout()
{
lv_paired_devices = (ListView)findViewById(R.id.lv_paired_devices);
adapter_paired_devices = new ArrayAdapter(getApplicationContext(),R.layout.support_simple_spinner_dropdown_item);
lv_paired_devices.setAdapter(adapter_paired_devices);
sendMessage=findViewById(R.id.send_button);
}
public void initialize_bluetooth()
{
bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (bluetoothAdapter == null) {
// Device doesn't support Bluetooth
Toast.makeText(getApplicationContext(),"Your Device doesn't support bluetooth. you can play as Single player",Toast.LENGTH_SHORT).show();
finish();
}
//Add these permisions before
// <uses-permission android:name="android.permission.BLUETOOTH" />
// <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
// <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
// <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
if (!bluetoothAdapter.isEnabled()) {
Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
}
else {
set_pairedDevices = bluetoothAdapter.getBondedDevices();
if (set_pairedDevices.size() > 0) {
for (BluetoothDevice device : set_pairedDevices) {
String deviceName = device.getName();
String deviceHardwareAddress = device.getAddress(); // MAC address
adapter_paired_devices.add(device.getName() + "\n" + device.getAddress());
}
}
}
}
public class AcceptThread extends Thread
{
private final BluetoothServerSocket serverSocket;
public AcceptThread() {
BluetoothServerSocket tmp = null;
try {
// MY_UUID is the app's UUID string, also used by the client code
tmp = bluetoothAdapter.listenUsingRfcommWithServiceRecord("NAME",MY_UUID);
} catch (IOException e) { }
serverSocket = tmp;
}
public void run() {
BluetoothSocket socket = null;
// Keep listening until exception occurs or a socket is returned
while (true) {
try {
socket = serverSocket.accept();
} catch (IOException e) {
break;
}
// If a connection was accepted
if (socket != null)
{
// Do work to manage the connection (in a separate thread)
mHandler.obtainMessage(CONNECTED).sendToTarget();
}
}
}
}
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
bluetoothAdapter.cancelDiscovery();
try {
// Connect the device through the socket. This will block
// until it succeeds or throws an exception
mHandler.obtainMessage(CONNECTING).sendToTarget();
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)
// bluetooth_message = "Initial message"
// mHandler.obtainMessage(MESSAGE_WRITE,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 = new byte[2]; // 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);
// Send the obtained bytes to the UI activity
mHandler.obtainMessage(MESSAGE_READ, bytes, -1, buffer).sendToTarget();
Toast.makeText(BluetoothActivity.this,bytes,Toast.LENGTH_LONG).show();
} catch (IOException e) {
break;
}
}
}
/* Call this from the main activity to send data to the remote device */
public void write(byte[] bytes) {
sendMessage.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
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) { }
}
}
I followed a Bluetooth tutorial video on how to create a connection using my app with other Bluetooth devices.
However, I am unable to connect to the devices directly on the app itself. I was expecting the code to allow me to do something like "Connecting..." once I tap on the device name I want to engage a connection with.
Below is my Bluetooth code:
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.DialogInterface;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Handler;
import android.os.Message;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.support.v7.internal.widget.AdapterViewCompat;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
//import android.widget.Button;
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 Bluetooth extends Activity implements AdapterView.OnItemClickListener {
ArrayAdapter<String> listAdapterBt;
ListView listViewBt;
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){
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());
break;
case MESSAGE_READ:
byte[] readBuf = (byte[])msg.obj;
String string = new String(readBuf);
Toast.makeText(getApplicationContext(), "CONNECT", Toast.LENGTH_SHORT).show();
break;
}
}
};
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_bluetooth);
init(); //initiate Bluetooth
if (btAdapter == null){
Toast.makeText(getApplicationContext(), "No bluetooth detected",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() {
devicesArray = btAdapter.getBondedDevices();
if (devicesArray.size() > 0){
//add devices in array to list array
for(BluetoothDevice device:devicesArray){
pairedDevices.add(device.getName());
}
}
}
private void init() {
listViewBt = (ListView)findViewById(R.id.listViewBt);
listViewBt.setOnItemClickListener(this);
listAdapterBt = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1,0);
listViewBt.setAdapter(listAdapterBt);
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))) {
//append
s = "Paired";
break;
}
}
// matt-hp (paired)
listAdapterBt.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);
IntentFilter 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 (requestCode == RESULT_CANCELED){
Toast.makeText(getApplicationContext(), "Bluetooth must be enabled to continue", Toast.LENGTH_SHORT).show();
finish();
}
}
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
if(btAdapter.isDiscovering()){
btAdapter.cancelDiscovery();
}
if (listAdapterBt.getItem(position).contains("Paired")){
BluetoothDevice selectedDevice = devices.get(position);
ConnectThread connect = new ConnectThread(selectedDevice);
connect.start();
Toast.makeText(getApplicationContext(), "device is paired", Toast.LENGTH_SHORT).show();
}
else{
Toast.makeText(getApplicationContext(), "device is not paired", Toast.LENGTH_SHORT).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
btAdapter.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)
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) { }
}
}
}
Below is my bluetooth.xml code:
<menu xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
tools:context="com.mdpgrp10.androidmobilecontrollermodule.Bluetooth">
<item android:id="#+id/action_settings" android:title="#string/action_settings"
android:orderInCategory="100" app:showAsAction="never" />
</menu>
Just hoping for any help in any way. Much appreciated!
I am implementing a simple app that sends and receives data between two devices via bluetooth.
I am following the android developer's blog's bluetoothchat example, but my application seems unable to read from the inputstream of a socket.
Writing to the socket is fine. The app does not throw an error nor update the textview as it is supposed to. Any help would be appreciated. Thank you!
Main activity.java(where list of devices are shown and selected) - probably not the errored file:
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.bluetooth.*;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Set;
import java.util.UUID;
public class MainActivity extends ActionBarActivity {
private final static int REQUEST_ENABLE_BT = 22;
private static final UUID MY_UUID = UUID.fromString("fa87c0d0-afac-11de-8a39-0800200c9a66");
private static final String NAME = "Bluetooth!";
ListView listView;
ArrayList<BluetoothDevice> deviceList;
ArrayAdapter<String> arrayAdapter;
ScanReciever reciever;
BluetoothAdapter bluetooth_adapter;
Button onButton;
Button scanButton;
Button alreadyButton;
AcceptThread acceptThread;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
deviceList = new ArrayList<>();
//arrayAdapter = new ArrayAdapter<>(this, R.xml.table_item, android.R.id.text1, deviceList);
arrayAdapter = new ArrayAdapter<String>(this, R.layout.table_item);
// Set up Buttons
onButton = (Button) findViewById(R.id.onButton);
scanButton = (Button) findViewById(R.id.scanButton);
onButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
askAdapterOn();
}
});
scanButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
scanForDevices();
}
});
// Set up listview
listView = (ListView) findViewById(R.id.listView);
listView.setAdapter(arrayAdapter);
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> arg0, View v, int position, long id) {
callButtons(deviceList.get(position));
}
});
// Bluetooth setup.
bluetooth_adapter = BluetoothAdapter.getDefaultAdapter();
// If device is incapable of using bluetooth:
if (bluetooth_adapter == null) {
onButton.setEnabled(false);
scanButton.setEnabled(false);
}
else if (!bluetooth_adapter.isEnabled()) { // If bluetooth is off:
//Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
//startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
onButton.setEnabled(true);
scanButton.setEnabled(false);
}
else { // Bluetooth is on and ready:
onButton.setEnabled(false);
scanButton.setEnabled(true);
alreadyButton = (Button) findViewById(R.id.alreadyButton);
alreadyButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// Collect current devices into a set.
Set<BluetoothDevice> pairedDevices = bluetooth_adapter.getBondedDevices();
// Pass the index of the paired device
if (pairedDevices.size() > 0) {
callButtons(pairedDevices.iterator().next()); // First element in set.
} else {
System.out.println("No paired Device!");
}
}
});
acceptThread = new AcceptThread();
acceptThread.start();
}
}
private class ScanReciever extends BroadcastReceiver {
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if (BluetoothAdapter.ACTION_DISCOVERY_STARTED.equals(action)) {
System.out.println("Started");
//discovery starts, we can show progress dialog or perform other tasks
} else if (BluetoothAdapter.ACTION_DISCOVERY_FINISHED.equals(action)) {
System.out.println("finished");
//discovery finishes, dismis progress dialog
} else if (BluetoothDevice.ACTION_FOUND.equals(action)) {
//bluetooth device found
BluetoothDevice device = (BluetoothDevice) intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
System.out.println("FOUND: " + device.getName());
deviceList.add(device);
arrayAdapter.add(device.getName()+" - Click to pair");
arrayAdapter.notifyDataSetChanged();
} else if (BluetoothDevice.ACTION_BOND_STATE_CHANGED.equals(action)) {
System.out.println("Connected~!!!!!!!!!!!!!!");
callButtons(deviceList.get(deviceList.size()-1));
}
}
};
protected void askAdapterOn() {
Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
}
protected void scanForDevices() {
IntentFilter filter = new IntentFilter();
filter.addAction(BluetoothDevice.ACTION_FOUND);
filter.addAction(BluetoothAdapter.ACTION_DISCOVERY_STARTED);
filter.addAction(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);
reciever = new ScanReciever();
registerReceiver(reciever, filter);
bluetooth_adapter.startDiscovery();
}
protected void callButtons(BluetoothDevice bd) {
bluetooth_adapter.cancelDiscovery();
Intent toButton = new Intent(getApplicationContext(), buttons.class);
toButton.putExtra("selected",bd);
startActivity(toButton);
}
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == REQUEST_ENABLE_BT) {
if (resultCode == RESULT_OK){
if (bluetooth_adapter.isEnabled()){
onButton.setEnabled(false);
scanButton.setEnabled(true);
}
else {
onButton.setEnabled(true);
scanButton.setEnabled(false);
}
}
}
}
#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);
}
#Override
public void onDestroy() {
unregisterReceiver(reciever);
super.onDestroy();
}
private class AcceptThread extends Thread {
private final BluetoothServerSocket mmServerSocket;
public AcceptThread() {
// Use a temporary object that is later assigned to mmServerSocket,
// because mmServerSocket is final
BluetoothServerSocket tmp = null;
try {
// MY_UUID is the app's UUID string, also used by the client code
tmp = bluetooth_adapter.listenUsingRfcommWithServiceRecord(NAME, MY_UUID);
System.out.println("READY TO ACCEPT");
} catch (IOException e) { }
mmServerSocket = tmp;
}
public void run() {
BluetoothSocket socket = null;
// Keep listening until exception occurs or a socket is returned
while (true) {
try {
socket = mmServerSocket.accept();
} catch (IOException e) {
break;
}
// If a connection was accepted
if (socket != null) {
// Do work to manage the connection (in a separate thread)
//manageConnectedSocket(socket);
try {
mmServerSocket.close();
} catch (IOException e) { }
break;
}
}
}
/** Will cancel the listening socket, and cause the thread to finish */
public void cancel() {
try {
mmServerSocket.close();
} catch (IOException e) { }
}
}
}
Buttons.java(where the app will initiate a connection and maintain communication) - probably the file with the error:
import android.app.Activity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.lang.reflect.Method;
import java.util.UUID;
public class buttons extends Activity {
public static final int MESSAGE_READ = 2;
public static final int MESSAGE_WRITE = 3;
BluetoothDevice selected;
BluetoothAdapter bluetoothAdapter;
TextView tv;
Button button1;
Button button2;
Button button3;
Button unpairB;
private static final UUID MY_UUID = UUID.fromString("fa87c0d0-afac-11de-8a39-0800200c9a66");
ConnectThread connectThread;
ConnectedThread connectedThread;
BluetoothSocket mmSocket;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.buttons);
bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
selected = getIntent().getExtras().getParcelable("selected");
pair(selected);
connectedThread = null;
try {
connectedThread = new ConnectedThread(mmSocket);
connectedThread.start();
System.out.println("ConnectedThread started!");
} catch (Exception e) {
Log.e("unpair()", e.getMessage());
}
// Set up Buttons
button1 = (Button) findViewById(R.id.button1);
button2 = (Button) findViewById(R.id.button2);
button3 = (Button) findViewById(R.id.button3);
unpairB = (Button) findViewById(R.id.unpairButton);
button1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
buttonPressed(1);
}
});
button2.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
buttonPressed(2);
}
});
button3.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
buttonPressed(3);
}
});
unpairB.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
unpair(selected);
finish();
}
});
// Set up textview
tv = (TextView) findViewById(R.id.textView);
tv.setText("connected to: " + selected.getName());
}
protected void buttonPressed(int i) {
connectedThread.write(i);
tv.setText(Integer.toString(i));
}
private void pair(BluetoothDevice device) {
connectThread = new ConnectThread(device);
connectThread.start();
}
private void unpair(BluetoothDevice device) {
try {
Method m = device.getClass().getMethod("removeBond", (Class[]) null);
m.invoke(device, (Object[]) null);
} catch (Exception e) {
Log.e("unpair()", e.getMessage());
}
}
private class ConnectThread extends Thread {
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);
System.out.println("Socket was created in ConnectThread");
} catch (IOException e) { }
mmSocket = tmp;
}
public void run() {
// Cancel discovery because it will slow down the connection
// bluetoothAdapter.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);
}
/** 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 bluetoothSocket;
private final InputStream inputStream;
private final OutputStream outputStream;
public ConnectedThread(BluetoothSocket socket) {
this.bluetoothSocket = socket;
InputStream tmpIn = null;
OutputStream tmpOut = null;
System.out.println("Connected to " + socket.getRemoteDevice().getName());
try {
tmpIn = bluetoothSocket.getInputStream();
tmpOut = bluetoothSocket.getOutputStream();
} catch (IOException e) {
}
inputStream = tmpIn;
outputStream = tmpOut;
}
public void run() {
byte[] buffer = new byte[1024];
int bytes;
if (inputStream == null) System.out.println("Inputstream is null");
else System.out.println("Inputstream is safe");
if (outputStream == null) System.out.println("outstream is null");
else System.out.println("Outputstream is safe");
while (true) {
try {
System.out.println("Blocking?");
bytes = inputStream.read(buffer);
System.out.println("NO");
handler.obtainMessage(MESSAGE_READ, bytes, -1,
buffer).sendToTarget();
} catch (IOException e) {
break;
}
}
}
public void write(int i) {
try {
byte[] buffer = new byte[1024];
buffer[0] = (byte) i;
outputStream.write(buffer);
outputStream.flush();
handler.obtainMessage(MESSAGE_WRITE, -1, -1,
buffer).sendToTarget();
System.out.println("Write SUCCESS!!!!!!!!!!!!!!");
} catch (IOException e) {
System.out.println("write ERRORRRRRRRRRRRRRRRRR");
}
}
public void cancel() {
try {
bluetoothSocket.close();
} catch (IOException e) {
}
}
}
private final Handler handler = new Handler() {
#Override
public void handleMessage(Message msg) {
switch (msg.what) {
case MESSAGE_WRITE:
System.out.println("Write was broadcasted");
byte[] writeBuf = (byte[]) msg.obj;
String writeMessage = new String(Integer.toString(writeBuf[0]));
///tv.setText(writeMessage);
break;
case MESSAGE_READ:
System.out.println("Read was broadcasted");
byte[] readBuf = (byte[]) msg.obj;
String readMessage = new String(Integer.toString(readBuf[0]));
tv.setText(readMessage);
break;
}
}
};
}
I am developing an android application which transmits queries to a bluetooth device and retrieves data from it. In the app, a connection is established by tapping on an available device in the upper part of the screen, and then there's a button on the bottom half which triggers the sending of the query and the text box next to it displays the data.
I am able to successfully connect to the device and fetch data from it once, but when I hit the query button the second time around, the app crashes.
In the code I start the ConnectedThread thread once I hit the button, and then at the end of the thread code a handler is called which then displays the text on the screen. The second time I hit the button my code tries to start the same thread again - this causes the error. I have been trying out to a way to stop the connectedThread once the received data is received, this way I can start and close the connectedThread for every transmit-receive.
Can you please suggest a solution to the issue or a way to improvise the code structure. Any help will be appreciated.
Thanks
package com.test.bluetooth;
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.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.Button;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
public class Main_Activity extends Activity implements OnItemClickListener {
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;
BluetoothAdapter btAdapter;
Set<BluetoothDevice> devicesArray;
ArrayList<String> pairedDevices;
ArrayList<BluetoothDevice> devices;
ArrayAdapter<String> listAdapter;
ListView listView;
Button mConnect;
TextView mResponse;
IntentFilter filter;
BroadcastReceiver receiver;
String tag = "Debug";
Handler mHandler = new Handler(){
#Override
public void handleMessage(Message msg) {
// TODO Auto-generated method stub
Log.i(tag, "Handler starts");
super.handleMessage(msg);
switch(msg.what){
case SUCCESS_CONNECT:
final ConnectedThread connectedThread = new ConnectedThread((BluetoothSocket)msg.obj);
Toast.makeText(getApplicationContext(), "Connected", 0).show();
mConnect.setOnClickListener(
new View.OnClickListener()
{
public void onClick(View view)
{
//Log.v("EditText", mCommand.getText().toString());
//String Command = mCommand.getText().toString();
byte[] inputs = {0x30, 0x31, 0x30, 0x44, 0x0d, 0x0a};
connectedThread.write(inputs);
Log.i(tag, "sent ");
connectedThread.start();
Log.i(tag, "sent 2");
}
});
break;
case MESSAGE_READ:
byte[] TxBuf = (byte[])msg.obj;
String string = new String(TxBuf);
Log.d("ReceiverValue", string);
mResponse.setText(string);
break;
}
}
};
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", 0).show();
}
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
init();
if(btAdapter==null){
Toast.makeText(getApplicationContext(), "No bluetooth detected", 0).show();
finish();
}
else{
if(!btAdapter.isEnabled()){
turnOn();
}
getPairedDevices();
startDiscovery();
}
}
private void startDiscovery() {
// TODO Auto-generated method stub
btAdapter.cancelDiscovery();
btAdapter.startDiscovery();
}
private void turnOn() {
// 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
listView=(ListView)findViewById(R.id.listView);
mConnect=(Button)findViewById(R.id.bConnectNew);
//mCommand=(EditText)findViewById(R.id.etCommand);
mResponse=(TextView)findViewById(R.id.tvResponse);
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) {
// 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)){
}
else if(BluetoothAdapter.ACTION_DISCOVERY_FINISHED.equals(action)){
}
else if(BluetoothAdapter.ACTION_STATE_CHANGED.equals(action)){
if(btAdapter.getState() == btAdapter.STATE_OFF){
turnOn();
}
}
}
};
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() {
// TODO Auto-generated method stub
super.onPause();
unregisterReceiver(receiver);
}
#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();
}
}
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(Main_Activity.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(Main_Activity.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) { }
}
}
}
The XML layout:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:text="Paired Devices"
android:id="#+id/tvPD"
/>
<ListView
android:id="#+id/listView"
android:layout_width="match_parent"
android:layout_height="100dip"
android:layout_above="#+id/Border"
android:layout_below="#+id/tvPD" >
</ListView>
<Button
android:id="#+id/bConnectNew"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBaseline="#+id/tvResponse"
android:layout_alignBottom="#+id/tvResponse"
android:layout_alignParentLeft="true"
android:layout_marginLeft="45dp"
android:text="Send" />
<TextView
android:id="#+id/tvResponse"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentRight="true"
android:layout_marginBottom="188dp"
android:layout_marginRight="26dp"
android:text="Response displayed here" />
<View
android:id="#+id/Border"
android:layout_width="wrap_content"
android:layout_height="3dip"
android:layout_alignParentLeft="true"
android:layout_centerVertical="true"
android:layout_weight="10"
android:background="#android:color/black" />
</RelativeLayout>
enter code here
I've been working on a program that listens for bluetooth messages to start various apps on my phone. Each of the following work correctly if the main layout is displayed but once one of the commands is called the other does not react properly. Here is the code for the two commands:
if (readMessage.equals("Button"))
{
Intent i = new Intent(Intent.ACTION_MAIN);
PackageManager manager = getPackageManager();
i = manager.getLaunchIntentForPackage("com.google.android.apps.maps");
Log.d("Main","i is: "+ i);
i.addCategory(Intent.CATEGORY_LAUNCHER);
startActivity(i);
Log.d("Main","Map pushed");
}
if (readMessage.equals("Home"))
{
Intent startMain = new Intent(Intent.ACTION_MAIN);
startMain.addCategory(Intent.CATEGORY_HOME);
startMain.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(startMain);
Log.d("Main","Home pushed");
}
So for example the message home is sent, the app will display the home screen. However if after the home screen is displayed and the message "Button" is sent nothing happens, but I know that the code is called from the Log.
Do I need to put my message handler into it's own service?
Here are the two java files:
Main:
package com.lorenjz.phoneremotefive;
import java.lang.Thread.State;
import java.util.ArrayList;
import java.util.Set;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.app.Activity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.content.ComponentName;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.SharedPreferences.OnSharedPreferenceChangeListener;
import android.content.pm.PackageManager;
import android.util.Log;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.AdapterView;
import android.widget.Button;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
import android.preference.PreferenceActivity;
import android.preference.PreferenceManager;
public class MainRemote extends Activity {
private static TextView btstatus=null;
private Button closeButt;
private TextView ringtone=null;
private TextView checkbox2=null;
private Boolean serverState = false;
//declerations:
private BluetoothAdapter btAdapter;
public ArrayList myArray;
public ArrayList devArray;
private int myContext;
private BlueStuff mChatService = null;
// Message types sent from the BluetoothChatService Handler
public static final int MESSAGE_STATE_CHANGE = 1;
public static final int MESSAGE_READ = 2;
public static final int MESSAGE_WRITE = 3;
public static final int MESSAGE_DEVICE_NAME = 4;
public static final int MESSAGE_TOAST = 5;
public static final String DEVICE_NAME = "device_name";
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main_remote);
btstatus=(TextView)findViewById(R.id.btstatus);
closeButt=(Button)findViewById(R.id.close);
/**checkbox=(TextView)findViewById(R.id.checkbox);
checkbox2=(TextView)findViewById(R.id.checkbox2);**/
SharedPreferences prefs=PreferenceManager
.getDefaultSharedPreferences(this);
//checkbox.setText(new Boolean(prefs.getBoolean("checkbox", false))
// .toString());
Boolean servState = (new Boolean(prefs.getBoolean("serverstate", false)).booleanValue());
if (servState = true){
Log.d("Main","It thinks the server should be on");
//checkbox2.setText(new Boolean(prefs.getBoolean("checkbox2", false))
// .toString());
mChatService = new BlueStuff(getBaseContext(), mHandler);
int stateString = mChatService.getState();
Log.d("Main","chat service: " + stateString);
//+ mChatService.getState()
mChatService.start();
}
int stateString = mChatService.getState();
Log.d("Main","After stuff happens. chat service: " + stateString);
btstatus.setText("No Connection yet");
setupUI();
closeButt.setOnClickListener(new OnClickListener(){
public void onClick(View v) {
mChatService.stop();
}
});
}
#Override
public void onResume() {
super.onResume();
SharedPreferences prefs=PreferenceManager
.getDefaultSharedPreferences(this);
//checkbox.setText(new Boolean(prefs.getBoolean("checkbox", false))
// .toString());
String servState = (new Boolean(prefs.getBoolean("serverstate", false)).toString());
Log.d("Main","Server State: " +servState);
//checkbox2.setText(new Boolean(prefs.getBoolean("checkbox2", false))
// .toString());
// Performing this check in onResume() covers the case in which BT was
// not enabled during onStart(), so we were paused to enable it...
// onResume() will be called when ACTION_REQUEST_ENABLE activity returns.
if (mChatService != null) {
// Only if the state is STATE_NONE, do we know that we haven't started already
if (mChatService.getState() == BlueStuff.STATE_NONE) {
// Start the Bluetooth chat services
mChatService.start();
startService(new Intent(this, BlueStuff.class));
}
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.activity_main_remote, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.menu_settings:
startActivity(new Intent(this, PreferencesB.class));
return true;
}
return(super.onOptionsItemSelected(item));
}
public void setupUI(){
}
private final Handler mHandler = new Handler() {
#Override
public void handleMessage(Message msg) {
switch (msg.what) {
case MESSAGE_STATE_CHANGE:
//if(D) Log.i("Main", "MESSAGE_STATE_CHANGE: " + msg.arg1);
switch (msg.arg1) {
case BlueStuff.STATE_CONNECTED:
Toast.makeText(getApplicationContext(), "Connected", Toast.LENGTH_SHORT).show();
//setStatus(getString(R.string.title_connected_to, mConnectedDeviceName));
//mConversationArrayAdapter.clear();
break;
case BlueStuff.STATE_CONNECTING:
Toast.makeText(getApplicationContext(), "Connecting", Toast.LENGTH_SHORT).show();
//setStatus(R.string.title_connecting);
break;
case BlueStuff.STATE_LISTEN:
Toast.makeText(getApplicationContext(), "Listening", Toast.LENGTH_SHORT).show();
break;
case BlueStuff.STATE_NONE:
//setStatus(R.string.title_not_connected);
break;
}
break;
/**case MESSAGE_WRITE:
byte[] writeBuf = (byte[]) msg.obj;
// construct a string from the buffer
String writeMessage = new String(writeBuf);
mConversationArrayAdapter.add("Me: " + writeMessage);
break;**/
case MESSAGE_READ:
byte[] readBuf = (byte[]) msg.obj;
// construct a string from the valid bytes in the buffer
String readMessage = new String(readBuf, 0, msg.arg1);
//mConversationArrayAdapter.add(mConnectedDeviceName+": " + readMessage);
//Toast.makeText(getApplicationContext(), "Message: " + readMessage, Toast.LENGTH_SHORT).show();
if (readMessage.equals("Button"))
{
/**Intent startMain = new Intent(Intent.ACTION_MAIN);
startMain.addCategory(Intent.CATEGORY_HOME);
startMain.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(startMain);**/
Intent i = new Intent(Intent.ACTION_MAIN);
PackageManager manager = getPackageManager();
i = manager.getLaunchIntentForPackage("com.google.android.apps.maps");
Log.d("Main","i is: "+ i);
i.addCategory(Intent.CATEGORY_LAUNCHER);
startActivity(i);
Log.d("Main","Map pushed");
/**Intent launch_intent = new Intent("android.intent.action.MAIN");
launch_intent.addCategory("android.intent.category.LAUNCHER");
launch_intent.setComponent(new ComponentName("com.google.android.maps", "map"));
launch_intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(launch_intent);**/
}
if (readMessage.equals("Home"))
{
Intent startMain = new Intent(Intent.ACTION_MAIN);
startMain.addCategory(Intent.CATEGORY_HOME);
startMain.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(startMain);
Log.d("Main","Home pushed");
}
break;
/**case MESSAGE_DEVICE_NAME:
// save the connected device's name
mConnectedDeviceName = msg.getData().getString(DEVICE_NAME);
Toast.makeText(getApplicationContext(), "Connected to "
+ mConnectedDeviceName, Toast.LENGTH_SHORT).show();
break;
case MESSAGE_TOAST:
Toast.makeText(getApplicationContext(), msg.getData().getString(TOAST),
Toast.LENGTH_SHORT).show();
break;**/
}
}
};
final static void updateBTStatus(int mState){
Log.d("Main", "update called. mState is: " + mState);
btstatus.setText("prior to switch");
statusTry();
switch(mState){
case 1:
btstatus.setText("Listening for connection");
Log.d("Main","Status should be listening for connection");
case 2:
btstatus.setText("Connecting");
case 3:
btstatus.setText("Connected");
}
}
public static void statusTry(){
btstatus.setText("post switch try");
}
}
Blue Stuff:
package com.lorenjz.phoneremotefive;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.UUID;
import android.app.Service;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothServerSocket;
import android.bluetooth.BluetoothSocket;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.os.Handler;
import android.os.IBinder;
import android.os.Message;
import android.util.Log;
import android.widget.Toast;
public class BlueStuff extends Service{
private static final String TAG = "Blue";
private static final boolean D = true;
private final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
private final String NAME = "Zimmer";
//private BluetoothAdapter mBluetoothAdapter;
private final BluetoothAdapter mAdapter;
private final Handler mHandler;
private int mState;
public static final int STATE_NONE = 0; // we're doing nothing
public static final int STATE_LISTEN = 1; // now listening for incoming connections
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
private ConnectThread mConnectThread;
private ConnectedThread mConnectedThread;
private AcceptThread mSecureAcceptThread;
private AcceptThread mInsecureAcceptThread;
/**
* Constructor. Prepares a new BluetoothChat session.
* #param context The UI Activity Context
* #param handler A Handler to send messages back to the UI Activity
*/
public BlueStuff(Context context, Handler handler) {
mAdapter = BluetoothAdapter.getDefaultAdapter();
mState = STATE_NONE;
mHandler = handler;
}
/**
* Return the current connection state. */
public synchronized int getState() {
return mState;
}
/**
* Start the chat service. Specifically start AcceptThread to begin a
* session in listening (server) mode. Called by the Activity onResume() */
public synchronized void start() {
if (D) Log.d(TAG, "start");
// Cancel any thread attempting to make a connection
if (mConnectThread != null) {mConnectThread.cancel(); mConnectThread = null;}
// Cancel any thread currently running a connection
if (mConnectedThread != null) {mConnectedThread.cancel(); mConnectedThread = null;}
setState(STATE_LISTEN);
if (mInsecureAcceptThread == null) {
mInsecureAcceptThread = new AcceptThread();
mInsecureAcceptThread.start();
}
}
public void stop(){
mConnectedThread.cancel();
}
/**
* Set the current state of the chat connection
* #param state An integer defining the current connection state
*/
private synchronized void setState(int state) {
if (D) Log.d(TAG, "setState() " + mState + " -> " + state);
mState = state;
// Give the new state to the Handler so the UI Activity can update
mHandler.obtainMessage(MainRemote.MESSAGE_STATE_CHANGE, state, -1).sendToTarget();
}
class AcceptThread extends Thread {
private final BluetoothServerSocket mmServerSocket;
public AcceptThread() {
// Use a temporary object that is later assigned to mmServerSocket,
// because mmServerSocket is final
BluetoothServerSocket tmp = null;
try {
// MY_UUID is the app's UUID string, also used by the client code
//tmp = mAdapter.listenUsingRfcommWithServiceRecord(NAME, MY_UUID);
tmp = mAdapter.listenUsingRfcommWithServiceRecord(NAME, MY_UUID);
} catch (IOException e) { }
Log.d("Blue","Listen Failed tmp 1c: " + tmp);
mmServerSocket = tmp;
Log.d("Blue","mmServerSocket 1: " + mmServerSocket);
MainRemote.updateBTStatus(mState);
}
public void run() {
Log.d("Blue","Run Called");
BluetoothSocket socket = null;
// Keep listening until exception occurs or a socket is returned
while (true) {
try {
Log.d("Blue","mmServerSocket 2: " + mmServerSocket);
socket = mmServerSocket.accept();
}
catch (IOException e) {
break;
}
// If a connection was accepted
/** if (socket != null) {
// Do work to manage the connection (in a separate thread)
//manageConnectedSocket(socket);
//mmServerSocket.close();
Log.d("Blue","Connection was accepted");
MainRemote.updateBTStatus(mState);
break;
}**/
if (socket != null) {
synchronized (BlueStuff.this) {
switch (mState) {
case STATE_LISTEN:
case STATE_CONNECTING:
// Situation normal. Start the connected thread.
connected(socket, socket.getRemoteDevice());
break;
case STATE_NONE:
case STATE_CONNECTED:
// Either not ready or already connected. Terminate new socket.
try {
socket.close();
} catch (IOException e) {
Log.e(TAG, "Could not close unwanted socket", e);
}
break;
}
}
}
}
}
/** Will cancel the listening socket, and cause the thread to finish */
public void cancel() {
try {
mmServerSocket.close();
} catch (IOException e) { }
}
}
class ConnectThread extends Thread {
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
mAdapter.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);
}
/** Will cancel an in-progress connection, and close the socket */
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) { }
}
}
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 = new byte[1024]; // 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);
// Send the obtained bytes to the UI activity
mHandler.obtainMessage(MainRemote.MESSAGE_READ, bytes, -1, buffer)
.sendToTarget();
Log.d("Blue","message recieved!: " + bytes);
} 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) { }
}
}
/**
* Start the ConnectedThread to begin managing a Bluetooth connection
* #param socket The BluetoothSocket on which the connection was made
* #param device The BluetoothDevice that has been connected
*/
public synchronized void connected(BluetoothSocket socket, BluetoothDevice
device) {
//if (D) Log.d(TAG, "connected, Socket Type:" + socketType);
// Cancel the thread that completed the connection
if (mConnectThread != null) {mConnectThread.cancel(); mConnectThread = null;}
// Cancel any thread currently running a connection
if (mConnectedThread != null) {mConnectedThread.cancel(); mConnectedThread = null;}
// Cancel the accept thread because we only want to connect to one device
if (mSecureAcceptThread != null) {
mSecureAcceptThread.cancel();
mSecureAcceptThread = null;
}
if (mInsecureAcceptThread != null) {
mInsecureAcceptThread.cancel();
mInsecureAcceptThread = null;
}
// Start the thread to manage the connection and perform transmissions
mConnectedThread = new ConnectedThread(socket);
mConnectedThread.start();
// Send the name of the connected device back to the UI Activity
Message msg = mHandler.obtainMessage(MainRemote.MESSAGE_DEVICE_NAME);
Bundle bundle = new Bundle();
bundle.putString(MainRemote.DEVICE_NAME, device.getName());
msg.setData(bundle);
mHandler.sendMessage(msg);
setState(STATE_CONNECTED);
}
#Override
public IBinder onBind(Intent intent) {
// TODO Auto-generated method stub
return null;
}
}
Its not that nothing is happening. Its that the Activity is not recreated. Try overriding onStart() I bet this is getting called instead.