我编写了一个基于bluetoothChat的简单应用程序。我使用 SPP 配置文件在手机和蓝牙模块之间进行通信。电话始终发起通信。该应用程序在 Android 4.2、Nexus 3 和 Samsung Galaxy 3 上完美运行。 更新到Android 4.3后，该应用程序不再运行。我一直在连接，我可以发送输出流并接收正确的数据，但在第一个输出流命令之后，应用程序总是在大约 6 秒后断开连接。 如下面的 logcat 所示，输入流上似乎存在计时器问题。
08-23 14:10:00.726: D/mems(23193): STEVAL-MKI106V1
08-23 14:10:00.804: D/Main Activity(23193): firmware version*setdb106V1
08-23 14:10:00.812: D/Main Activity(23193): sent message*setdb106V1
08-23 14:10:00.812: D/BluetoothMEMSCommunication(23193): dans write3
08-23 14:10:00.812: D/BluetoothMEMSCommunication(23193): envoi stream
08-23 14:10:05.812: W/bt-btif(20368): dm_pm_timer expires
08-23 14:10:05.812: W/bt-btif(20368): dm_pm_timer expires 0
08-23 14:10:05.812: W/bt-btif(20368): proc dm_pm_timer expires
08-23 14:10:11.656: E/bt-btm(20368): btm_sec_disconnected - Clearing Pending flag
08-23 14:10:11.656: W/bt-btif(20368): invalid rfc slot id: 15
08-23 14:10:11.656: I/connection(23193): connectionlost
什么是 dm_pm_timer？ 我尝试以不同的方式连接，使用安全和不安全的 rfcom。我知道蓝牙聊天没有优化接收缓冲区，所以我修改了它，不是没有效果。我也对输出流使用了flush命令，但也没有效果。
package com.meneujj.memsbtbis;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.UUID;
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;
import android.widget.Toast;
public class BluetoothMEMSCommunication {
// debugging
private static final String TAG = "BluetoothMEMSCommunication";
private static final boolean D = true;
// eMotion BT h as this standard UUID
private static final UUID STANDARD_UUID =
UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
// Member fields
private final BluetoothAdapter mAdapter;
private final Handler mHandler;
private int mState;
private int handlerCalling;
private ConnectThread mConnectThread;
private ConnectedThread mConnectedThread;
// Constants they indicate the current connection state
public static final int STATE_NONE = 0;
public static final int STATE_CONNECTED = 3; // now connected to a remote device
// constructor. Prepares a new Bluetooth Connection
// context The UI Activity Context
// handler an Handler to send messages back to the UI Activity
public BluetoothMEMSCommunication(Context context, Handler handler, int i) {
mAdapter = BluetoothAdapter.getDefaultAdapter();
mState = STATE_NONE;
mHandler = handler;
handlerCalling = i;
}
private synchronized void setState(int state) {
mState = state;
Log.d(TAG, Integer.toString(mState));
mHandler.obtainMessage(MainActivityMemsBT.MESSAGE_STATE_CHANGE, state, -1).sendToTarget();
}
public synchronized void connect(BluetoothDevice device) {
// start the thread to connect with the given device
if (mConnectThread != null) {
mConnectedThread.cancel();
mConnectedThread = null;
}
// cancel any thread currently running a connection
if (mConnectedThread != null) {
mConnectedThread.cancel();
mConnectedThread = null;
}
Log.d(TAG,"routine connect lancee");
mConnectThread = new ConnectThread(device);
mConnectThread.start();
}
private void ConnectionLost() {
// Send a failure message back to the activity
Message msg = mHandler.obtainMessage(MainActivityMemsBT.CONNECTION_LOST_MESSAGE);
Bundle bundle = new Bundle();
bundle.putString(MainActivityMemsBT.TOAST_CONNECTION_LOST, "Device connection was lost");
msg.setData(bundle);
mHandler.sendMessage(msg);
Log.i("connection","connectionlost");
setState(STATE_NONE);
StopAllThreads();
}
public synchronized void StopAllThreads() {
if (mConnectThread != null) {
mConnectThread.cancel();
mConnectThread = null;
}
if (mConnectedThread != null) {
mConnectedThread.cancel();
mConnectedThread = null;
}
setState(STATE_NONE);
}
public synchronized void connected(BluetoothSocket socket, BluetoothDevice device, final String socketType) {
// cancel the thread they 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 transmission
mConnectedThread = new ConnectedThread(socket, socketType);
mConnectedThread.start();
// Send the name of the connected device back to the UI activity
Message msg = mHandler.obtainMessage(MainActivityMemsBT.MESSAGE_DEVICE_NAME);
Bundle bundle = new Bundle();
bundle.putString(MainActivityMemsBT.DEVICE_NAME, device.getName());
msg.setData(bundle);
mHandler.sendMessage(msg);
setState(STATE_CONNECTED);
}
public void write(byte[] out) {
// create temporary object
ConnectedThread r;
Log.d(TAG,"dans write" + Integer.toString(mState));
// synchronize a copy of the ConnectedThread
synchronized (this) {
if (handlerCalling == 2) setState(STATE_CONNECTED);
if (mState != STATE_CONNECTED) {
Log.d(TAG, "different de STATE_CONNECTED");
Log.i(TAG, Integer.toString(handlerCalling));
return;}
r= mConnectedThread;
}
r.write(out);
}
知道有解决方法吗？或者我的代码中有任何明显的错误
谢谢
// Thread runs while attempting to an 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;
private String mSocketType;
public ConnectThread(BluetoothDevice device) {
mmDevice = device;
BluetoothSocket tmp = null;
try {
tmp = device.createRfcommSocketToServiceRecord(STANDARD_UUID);
//tmp = device.createInsecureRfcommSocketToServiceRecord(STANDARD_UUID);
/* try {
Method m = device.getClass().getMethod("createRfcommSocket", new Class[] {int.class});
try {
tmp = (BluetoothSocket) m.invoke(device, 1);
} catch (IllegalArgumentException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IllegalAccessException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (InvocationTargetException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
} catch (NoSuchMethodException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} */
} catch (IOException e) {
}
mmSocket = tmp;
}
public void run () {
setName("ConnectThread" + mSocketType);
mAdapter.cancelDiscovery();
try {
mmSocket.connect();
} catch (IOException e) {
try {
mmSocket.close();
} catch (IOException e2) {
Log.e(TAG, "unable to close() " + mSocketType + "socket during connection failure", e2);
}
return;
}
// reset the CoonectThread because the job is over
synchronized (BluetoothMEMSCommunication.this) {
mConnectThread = null;
}
connected(mmSocket, mmDevice, mSocketType);
}
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) {
}
}
// close connectThread class
}
private class ConnectedThread extends Thread {
private final BluetoothSocket mmSocket;
private final InputStream mmInStream;
private final OutputStream mmOutStream;
public ConnectedThread(BluetoothSocket socket, String socketType) {
mmSocket = socket;
InputStream tmpIn = null;
OutputStream tmpOut = null;
try {
tmpIn = socket.getInputStream();
tmpOut = socket.getOutputStream();
} catch (IOException e) {
ConnectionLost();
}
mmInStream = tmpIn;
mmOutStream = tmpOut;
}
// Thread to listen to input sockets
public void run() {
Log.i(TAG, "Begin mConnectedThread");
byte[] buffer = new byte[1024];
// int bytes;
int bytesRead = -1;
String message = "";
// keep listening to the InputStream while connected
while(true) {
try {
// read from the input stream
// bytesRead = mmInStream.read(buffer);
// message = message+ new String(buffer, 0, bytesRead);
// byte[] byteString = message.getBytes();
Log.i("info","pret a faire read");
bytesRead = mmInStream.read(buffer, 0, 1024);
if (bytesRead != -1 && handlerCalling == 1) {
mHandler.obtainMessage(MainActivityMemsBT.MESSAGE_READ, bytesRead, -1, buffer).sendToTarget(); }
if (bytesRead !=-1 && handlerCalling == 2) {
mHandler.obtainMessage(DemoAccelerometer.MESSAGE_READ, bytesRead, -1, buffer).sendToTarget(); }
}
catch (IOException e) {
ConnectionLost();
break;
}
}
}
public void write(byte[] buffer) {
try{
mmOutStream.write(buffer);
// if (handlerCalling == 1) {
// mHandler.obtainMessage(MainActivityMemsBT.MESSAGE_WRITE, -1, -1, buffer).sendToTarget();
Log.d(TAG,"envoi stream");
// mmOutStream.flush();
// }
} catch (IOException e) {
}
}
public void cancel() {
try{
mmSocket.close();
} catch (IOException e) {
}
}
}
}
从 Android 4.2 升级到 4.3 后，当从 Nexus 4 应用程序与外部蓝牙 ECG（医疗设备）通信时，我们可以在 6 秒后确认蓝牙断开。这种情况尤其发生在 ECG 测量期间，有大量入站数据（从 ECG 到 Android 应用程序）但没有出站数据。时不时地进行一些入站和出站数据的“正常”蓝牙通信似乎不会受到影响。
6 秒后，我们看到 JJM 报告的相同 adb 日志消息
dm_pm_timer expires
dm_pm_timer expires 0
proc dm_pm_timer expires
btm_sec_disconnected - Clearing Pending flag
Android 端的计时器到期会触发外部蓝牙 ECG 上的某些操作（因为没有出站数据而关闭输出流？），而外部蓝牙 ECG 又会发送我们在输入流上收到的 ECG 特定命令，而我们在 Android 4.2 的 Nexus 4 上从未收到过该命令.
更改 Android 应用程序实现以偶尔向 ECG 发送任意“保持活动”命令可以解决该问题。计时器到期不再出现在 adb 日志中，ECG 测量现在的行为与 Android 4.2 相同。
感谢JJM的提示。
我找到了解决方法。如果几秒钟内没有流活动，则会断开连接。我设法每秒进行几次输出或输入流，并且现在永远不会断开连接。
我在 StackOverflow 上找到了一个答案，帮助我解决了问题。我想这与输入流和输出流没有正确关闭和清空以及蓝牙套接字有关。使用此功能后：
* Reset input and output streams and make sure socket is closed.
* This method will be used during shutdown() to ensure that the connection is properly closed during a shutdown.
* @return
*/
private void resetConnection() {
setState(STATE_NONE);
Log.d(TAG, "reset connection");
if (mmInStream != null) {
try {
mmInStream.close();
} catch (Exception e) {
Log.d(TAG,"exception in closing inputstream - " + e.getMessage());
}
mmInStream = null;
}
if (mmOutStream != null) {
try {
mmOutStream.close();
} catch (Exception e) {
Log.d(TAG,"exception in closing outputstream - " + e.getMessage());
}
mmOutStream = null;
}
if (mmSocket != null) {
try {
mmSocket.close();
} catch (Exception e) {
Log.d(TAG,"exception in closing socket - " + e.getMessage());
}
mmSocket = null;
}
}
在 ConnectedThread 中并在必要时调用它，我消除了这个问题。从 inputStream 读取也可能出现问题，可能是因为尝试读取时其中没有任何内容。
我建议你做一个布尔函数readWrite()，每当你写入outputStream时，你也会读取inputStream并使用mHandler将readBuffer发送到UI。如果读取和写入都正常，则返回 true，如果其中之一出错则返回 false，并在关闭 ConnectedThread 之前使用 ResetConection。
它对我来说非常有效。
更新：（2013 年 9 月 30 日） 我正在运行我的应用程序，几分钟后仍然得到 hci_status = 36。我有一个应用程序，可以连接到外部蓝牙设备。我正在发送数据并接收数据大约。 3次/秒我在写入之间使用 Thread.sleep(300) 。在我的测试中，运行应用程序时，我会在几分钟到近 30 分钟后收到此错误。
如有任何反馈，我们将不胜感激！
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