我需要将我的android连接到蓝牙设备。我使用Google提供的BluetoothChat示例。
我使用Google Nexus进行此操作时遇到了一些麻烦，因为Nexus正在建立连接但是之后立即断开连接。我需要启动两次连接作为解决方法（请参阅connectionLost（））。
现在，它在Nexus One和HTC Desire上运行良好。
我的问题是应用程序退出时断开连接。它在Nexus上工作正常，连接关闭，但不在HTC Desire上。除了socket close之外，我还添加了inputstream / outputstream close函数。看看“stop（）”函数。
package xxx.yyy.zzz;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.lang.reflect.Method;
import java.util.UUID;
import activities.Act_Main;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.content.Context;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
/**
* This class does all the work for setting up and managing Bluetooth
* connections with other devices. It has a thread that listens for
* incoming connections, a thread for connecting with a device, and a
* thread for performing data transmissions when connected.
*/
public class BluetoothService {
// Debugging
private static final String TAG = "BluetoothService";
private static final boolean D = true;
// Member fields
//private final BluetoothAdapter mAdapter;
private final Handler mHandler;
private ConnectThread mConnectThread;
private ConnectedThread mConnectedThread;
private int mState;
private String mBTAddress;
private boolean isStop = false;
// Constants that indicate the current connection state
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
/**
* Constructor. Prepares a new Act_Main session.
* @param context The UI Activity Context
* @param handler A Handler to send messages back to the UI Activity
*/
public BluetoothService(Context context, Handler handler)
{
//mAdapter = BluetoothAdapter.getDefaultAdapter();
mState = STATE_NONE;
mHandler = handler;
}
/**
* Set the current state of the 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(Act_Main.MESSAGE_STATE_CHANGE, state, -1).sendToTarget();
}
/**
* Return the current connection state. */
public synchronized int getState()
{
return mState;
}
/**
* Start the ConnectThread to initiate a connection to a remote device.
* @param device The BluetoothDevice to connect
*/
public synchronized void connect(String BTAddress)
{
mBTAddress = BTAddress ;
// Get the BLuetoothDevice object
BluetoothDevice device = BluetoothAdapter.getDefaultAdapter().getRemoteDevice(BTAddress);
if (D) Log.d(TAG, "connect to: " + device);
// Cancel any thread attempting to make a connection
if (mState == STATE_CONNECTING)
if (mConnectThread != null) {mConnectThread.cancel(); mConnectThread = null;}
// Cancel any thread currently running a connection
if (mConnectedThread != null) {mConnectedThread.cancel(); mConnectedThread = null;}
// Start the thread to connect with the given device
mConnectThread = new ConnectThread(device);
mConnectThread.start();
setState(STATE_CONNECTING);
isStop = false ;
}
/**
* 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");
// 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;}
// 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(Act_Main.MESSAGE_DEVICE_NAME);
Bundle bundle = new Bundle();
bundle.putString(Act_Main.DEVICE_NAME, device.getName());
msg.setData(bundle);
mHandler.sendMessage(msg);
setState(STATE_CONNECTED);
}
/**
* Stop all threads
*/
public synchronized void stop()
{
isStop = true ;
if (D)
Log.d(TAG, "stop");
if(mConnectThread != null)
{
mConnectThread.cancel();
Thread moribund = mConnectThread;
mConnectThread = null;
moribund.interrupt();
}
if(mConnectedThread != null)
{
mConnectedThread.cancel();
Thread moribund = mConnectedThread;
mConnectedThread = null;
moribund.interrupt();
}
setState(STATE_NONE);
}
/**
* Write to the ConnectedThread in an unsynchronized manner
* @param out The bytes to write
* @see ConnectedThread#write(byte[])
*/
public void write(byte[] out)
{
// Create temporary object
ConnectedThread r;
// Synchronize a copy of the ConnectedThread
synchronized (this)
{
Log.d(TAG, "BT_SEND_MESSAGE");
if (mState != STATE_CONNECTED)
return;
r = mConnectedThread;
}
// Perform the write unsynchronized
r.write(out);
}
/**
* Indicate that the connection attempt failed and notify the UI Activity.
*/
private void connectionFailed()
{
try
{
synchronized (this)
{
this.wait(3000);
}
connect(mBTAddress);
}
catch(InterruptedException ex)
{
Log.e(TAG, "WAIT_EXCEPTION:"+ ex.getMessage());
}
}
/**
* Indicate that the connection was lost and notify the UI Activity.
*/
private void connectionLost()
{
if (!isStop)
connect(mBTAddress);
}
/**
* This thread runs while attempting to make an outgoing connection
* with a device. It runs straight through; the connection either
* succeeds or fails.
*/
private class ConnectThread extends Thread
{
private final BluetoothSocket mmSocket;
private final BluetoothDevice mmDevice;
public ConnectThread(BluetoothDevice device)
{
mmDevice = device;
BluetoothSocket tmp = null;
// Get a BluetoothSocket for a connection with the
// given BluetoothDevice
try
{
tmp = device.createRfcommSocketToServiceRecord(UUID.fromString("00001101-0000-1000-8000-00805F9B34FB"));
}
catch (Exception e)
{
Log.e(TAG, "create() failed", e);
}
mmSocket = tmp;
}
public void run()
{
Log.i(TAG, "BEGIN mConnectThread");
setName("ConnectThread");
// Always cancel discovery because it will slow down a connection
//mAdapter.cancelDiscovery();
// Make a connection to the BluetoothSocket
try
{
// This is a blocking call and will only return on a successful connection or an exception
mmSocket.connect();
}
catch (IOException e)
{
connectionFailed();
// Close the socket
try
{
mmSocket.close();
}
catch (IOException e2)
{
Log.e(TAG, "unable to close() socket during connection failure", e2);
}
return;
}
// Reset the ConnectThread because we're done
synchronized (BluetoothService.this)
{
mConnectThread = null;
}
// Start the connected thread
connected(mmSocket, mmDevice);
}
public void cancel()
{
try
{
mmSocket.close();
}
catch (IOException e)
{
Log.e(TAG, "close() of connect socket failed", e);
}
}
}
/**
* This thread runs during a connection with a remote device.
* It handles all incoming and outgoing transmissions.
*/
private class ConnectedThread extends Thread {
private BluetoothSocket mmSocket;
private InputStream mmInStream;
private OutputStream mmOutStream;
public ConnectedThread(BluetoothSocket socket) {
Log.d(TAG, "create ConnectedThread");
mmSocket = socket;
InputStream tmpIn = null;
OutputStream tmpOut = null;
// Get the BluetoothSocket input and output streams
try {
tmpIn = socket.getInputStream();
tmpOut = socket.getOutputStream();
} catch (IOException e) {
Log.e(TAG, "temp sockets not created", e);
}
mmInStream = tmpIn;
mmOutStream = tmpOut;
}
public void run()
{
Log.i(TAG, "BEGIN mConnectedThread");
byte[] buffer;
int bytes = 0;
// Keep listening to the InputStream while connected
while (true)
{
try
{
//Clear buffer
buffer = new byte[1024];
// Read from the InputStream
bytes = mmInStream.read(buffer);
// Send the obtained bytes to the UI Activity
mHandler.obtainMessage(Act_Main.MESSAGE_READ, bytes, -1, buffer).sendToTarget();
}
catch (IOException e)
{
//String bufferStr = new String(buffer, 0, buffer.length);
Log.e(TAG, "disconnected", e);
connectionLost();
break;
}
}
}
/**
* Write to the connected OutStream.
* @param buffer The bytes to write
*/
public void write(byte[] buffer)
{
try
{
mmOutStream.write(buffer);
}
catch (IOException e)
{
Log.e(TAG, "Exception during write", e);
}
}
public void cancel()
{
if (mmOutStream != null)
{
try {mmOutStream.close();} catch (Exception e) { Log.e(TAG, "close() of outputstream failed", e); }
mmOutStream = null;
}
if (mmInStream != null)
{
try {mmInStream.close();} catch (Exception e) { Log.e(TAG, "close() of inputstream failed", e); }
mmInStream = null;
}
if (mmSocket != null)
{
try {mmSocket.close();} catch (Exception e) { Log.e(TAG, "close() of connect socket failed", e); }
mmSocket = null;
}
}
}
}
提前感谢您的帮助。
JJ
答案 0 :(得分：1)
关于代码同步的快速评论：
在synchronized方法上保留connect()关键字，但是当需要连接时，请从线程中调用connect()，而不是从{{1}创建一个帖子}。就目前而言，您的代码正在从connect()触发连接线程，并且无法实现同步。 （目的是将请求同步到connect()，以便多个线程在尝试同时connect()时不会混淆。这可能会导致一些连接问题。
关于HTC：
我认为您和我遇到了同样的问题：Why can't HTC Droid running OTA 2.1 communicate with RFCOMM?
关于断开蓝牙连接的说明：
确保每次使用connect方法正常断开连接。
答案 1 :(得分：0)
我现在刚看完这篇文章：Bluetooth on 2.0+
有没有人能解决HTC Desire糟糕的实施问题？
更新：例如，我做了一个非常糟糕的解决方法。退出应用程序时，我会终止进程：
ActivityManager am = (ActivityManager) getSystemService(Context.ACTIVITY_SERVICE);
am.restartPackage("com.example.package");
我还在等待更清洁的解决方案。
答案 2 :(得分：0)
更新：似乎HTC通过他们的Froyo更新（android 2.2）
修复了它