我正在开发一个以蓝牙连接为核心部分的应用程序。目前该应用程序正在成功连接到蓝牙设备并与之通信。现在的主要问题是我们用来收集数据的设备在某些空闲状态后进入睡眠模式。
我的问题是，如何检测设备处于睡眠模式，以便我的应用程序可以要求用户唤醒设备？
我通过 SSP 连接。连接代码是 API 演示中蓝牙聊天应用程序的精确副本。
睡眠模式——我的应用程序连接到的设备（非移动设备）使用电池运行，因此如果 Android 应用程序在 1 分钟内没有对设备发出任何请求，则优化电池的使用设备进入睡眠模式。（可能已关闭不掉线）。所以我的应用程序需要捕获这种情况并让用户知道设备处于睡眠模式并将其唤醒，以便它可以响应应用程序请求。这是我可以解释睡眠模式的最佳方式。请记住蓝牙设备的睡眠模式，而不是安卓手机。
解决方案---我知道它并不完美，但我仍在努力……每当连接断开时，我都会收到套接字错误，因为远程设备处于睡眠模式或无法触及或死机。我还更改了我的代码，以便我不需要 UUID（现在它是低级连接）代码如下。
public class HHDBapiBTService {
// Debugging
private static final String TAG = "HHDBapiBTService";
private static final boolean D = true;
private BluetoothSocket mmSocket = null;
private InputStream mmInStream = null;
private OutputStream mmOutStream = null;
// Member fields
private final BluetoothAdapter mAdapter;
private Handler mHandler;
private ConnectThread mConnectThread;
private ConnectedThread mConnectedThread;
private int mState;
// 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
public static final int STATE_SLEEP = 4; // now connected to a remote
// device
/**
* 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 HHDBapiBTService(Context context, Handler handler) {
mAdapter = BluetoothAdapter.getDefaultAdapter();
mState = STATE_NONE;
mHandler = handler;
}
/**
* Set the current state of the chat connection
*
* @param state
* An integer defining the current connection state
*/
public 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(GlobalValues.MESSAGE_STATE_CHANGE, state, -1)
.sendToTarget();
}
/**
* Return the current connection state.
*/
public synchronized int getState() {
return mState;
}
public void setHandler(Handler handler) {
mHandler = handler;
}
/**
* 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);
}
/**
* Start the ConnectThread to initiate a connection to a remote device.
*
* @param device
* The BluetoothDevice to connect
*/
public synchronized void connect(BluetoothDevice device) {
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);
}
/**
* 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();
setState(STATE_CONNECTED);
}
/**
* Stop all threads
*/
public synchronized void stop() {
if (D)
Log.d(TAG, "stop");
if (mConnectThread != null) {
mConnectThread.cancel(true);
mConnectThread = null;
}
if (mConnectedThread != null) {
mConnectedThread.cancel();
mConnectedThread = null;
}
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) {
if(getState() == STATE_SLEEP){
connectionLost();
return;
}
// Create temporary object
ConnectedThread r;
// Synchronize a copy of the ConnectedThread
synchronized (this) {
if (mState != STATE_CONNECTED)
return;
r = mConnectedThread;
}
// Perform the write unsynchronized
r.write(out);
}
public void closeConnection(){
ConnectedThread r;
// Synchronize a copy of the ConnectedThread
synchronized (this) {
if (mState != STATE_CONNECTED)
return;
r = mConnectedThread;
}
r.cancel();
}
/**
* Indicate that the connection attempt failed and notify the UI Activity.
*/
private void connectionFailed() {
if(getState() != STATE_LISTEN){
setState(STATE_LISTEN);
// Send a failure message back to the Activity
Message msg = mHandler.obtainMessage(GlobalValues.MESSAGE_SHOW_TOAST);
Bundle bundle = new Bundle();
bundle.putString(GlobalValues.TOAST, "HHD device is in sleep mode or out-of range. Please shake the HHD device to make it active.");
msg.setData(bundle);
mHandler.sendMessage(msg);
}
}
/**
* Indicate that the connection was lost and notify the UI Activity.
*/
private void connectionLost() {
//setState(STATE_LISTEN);
// Send a failure message back to the Activity
/*Message msg = mHandler.obtainMessage(GlobalValues.MESSAGE_SHOW_TOAST);
Bundle bundle = new Bundle();
bundle.putString(GlobalValues.TOAST, "Device connection was lost");
msg.setData(bundle);
mHandler.sendMessage(msg);*/
setState(STATE_SLEEP);
Message msg = mHandler.obtainMessage(
GlobalValues.MESSAGE_REMOTE_DEVICE_LOST);
mHandler.sendMessage(msg);
}
/**
* 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 BluetoothSocket mmSocket;
private final BluetoothDevice mmDevice;
public ConnectThread(BluetoothDevice device) {
mmDevice = device;
}
@SuppressLint("NewApi")
protected boolean simpleComm(Integer port) {
// byte [] inputBytes = null;
// The documents tell us to cancel the discovery process.
mAdapter.cancelDiscovery();
Log.d(this.toString(), "Port = " + port);
try {
Method m = mmDevice.getClass().getMethod("createRfcommSocket",
new Class[] { int.class });
mmSocket = (BluetoothSocket) m.invoke(mmDevice, port);
// debug check to ensure socket was set.
assert (mmSocket != null) : "Socket is Null";
mAdapter.cancelDiscovery();
// attempt to connect to device
mmSocket.connect();
try {
Log.d(this.toString(),
"************ CONNECTION SUCCEES! *************");
// Reset the ConnectThread because we're done
/*synchronized (HHDBapiBTService.this) {
mConnectThread = null;
}*/
connected(mmSocket, mmDevice);
return true;
} finally {
// close the socket and we are done.
// //mmSocket.close();
}
// IOExcecption is thrown if connect fails.
} catch (IOException ex) {
Log.e(this.toString(), "IOException " + ex.getMessage());
if (port == 256) {
connectionFailed();
try {
mmSocket.close();
mmSocket = null;
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
} catch (NoSuchMethodException ex) {
Log.e(this.toString(),
"NoSuchMethodException " + ex.getMessage());
} catch (IllegalAccessException ex) {
Log.e(this.toString(),
"IllegalAccessException " + ex.getMessage());
} catch (InvocationTargetException ex) {
Log.e(this.toString(),
"InvocationTargetException " + ex.getMessage());
}catch (NullPointerException ex) {
Log.e(this.toString(),
"NullPointerException " + ex.getMessage());
}
return false;
}
public void run() {
for (Integer port = 1; port <= 256; port++) {
if (simpleComm(Integer.valueOf(port)))
break;
}
}
public void cancel() {
/*if (mmSocket != null) {
try {
mmSocket.close(); mmSocket = null;
} catch (IOException e) {
Log.e(TAG, "close() of connect secure socket failed", e);
}
}*/
}
public void cancel(boolean val) {
if (mmSocket != null) {
try {
mmSocket.close(); mmSocket = null;
} catch (IOException e) {
Log.e(TAG, "close() of connect secure 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 Logger logger;
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);
}
logger = Logger.getInstance();
mmInStream = tmpIn;
mmOutStream = tmpOut;
}
@Override
public void run() {
byte[] buffer = new byte[1024];
int bytes;
// Keep listening to the InputStream while connected
//Logic to parse the Inputstream
} catch (IOException e) {
HHDBapiBTService.this.stop();
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) {
connectionLost();
Log.e(TAG, "Exception during write", e);
}
}
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) {
Log.e(TAG, "close() of connect socket failed", e);
}
}
}
}