我遇到了问题而且我不知道如何解决它。我想创建服务，将传感器更改发送到客户端（线程）。
我有线程在哪里开始服务，客户端线程接收答案并通过蓝牙发送。问题是我无法处理服务。
public class SensorMsgService extends Service implements SensorEventListener{
public static final int MSG_SAY_HELLO = 1;
public static final int MSG_REGISTER_CLIENT = 1;
public static final int MSG_UNREGISTER_CLIENT = 2;
public static final int MSG_SET_VALUE = 3;
static final String TAG = "Sensor Msg Service";
ArrayList<Messenger> mClients = new ArrayList<Messenger>();
private SensorManager mSensorManager;
private Sensor mSensor;
private ArrayList<Float> temp;
private Looper mServiceLooper;
public class IncomingHandler extends Handler{
public IncomingHandler(Looper looper) {
super(looper);
}
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case MSG_REGISTER_CLIENT:
mClients.add(msg.replyTo);
break;
case MSG_UNREGISTER_CLIENT:
mClients.remove(msg.replyTo);
break;
case MSG_SET_VALUE:
//mValue = msg.arg1;
for (int i = mClients.size() - 1; i >= 0; i--) {
try {
/*mClients.get(i).send(
Message.obtain(null, MSG_SET_VALUE, 1, 0));*/
Log.d(TAG, "Message from client");
}
//catch (RemoteException e) {
catch (Exception e) {
// The client is dead. Remove it from the list;
// we are going through the list from back to front
// so this is safe to do inside the loop.
mClients.remove(i);
}
}
break;
default:
super.handleMessage(msg);
}
}
//Toast.makeText(getApplicationContext(), "Hello service test", Toast.LENGTH_SHORT).show();
}
final Messenger mMessenger = new Messenger(new IncomingHandler(mServiceLooper));
@Override
public IBinder onBind(Intent intent) {
// TODO Auto-generated method stub
Log.d(TAG, "binding");
//return null;
return mMessenger.getBinder();
}
@Override
public boolean bindService(Intent service, ServiceConnection conn, int flags) {
// TODO Auto-generated method stub
super.bindService(service, conn, flags);
// mServiceLooper.prepare();
temp = new ArrayList<Float>();
mSensorManager = (SensorManager) getSystemService(SENSOR_SERVICE);
mSensor = mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
mSensorManager.registerListener(this, mSensor, SensorManager.SENSOR_DELAY_NORMAL);
return true;
}
@Override
public void unbindService(ServiceConnection conn) {
// TODO Auto-generated method stub
super.unbindService(conn);
mSensorManager.unregisterListener(this);
}
@Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {
// TODO Auto-generated method stub
}
@Override
public void onSensorChanged(SensorEvent event) {
// TODO Auto-generated method stub
temp.add(event.values[0]);
temp.add(event.values[1]);
temp.add(event.values[2]);
for (int i = mClients.size() - 1; i >= 0; i--) {
try {
mClients.get(i).send(
Message.obtain(null, MSG_SET_VALUE, temp));
Log.d(TAG, "Message service to client sending");
}
//catch (RemoteException e) {
catch (Exception e) {
// The client is dead. Remove it from the list;
// we are going through the list from back to front
// so this is safe to do inside the loop.
mClients.remove(i);
}
}
}
}
我发起了这项服务，正如我在帖子中所说：
public class ConnectedThread extends Thread {
private final BluetoothSocket mmSocket;
private final InputStream mmInStream;
private final OutputStream mmOutStream;
private Context mContext;
/** Messenger for communicating with service. */
Messenger mService = null;
/** Flag indicating whether we have called bind on the service. */
boolean mIsBound;
ArrayList<Float> temp;
private Looper mServiceLooper;
public ConnectedThread(BluetoothSocket socket, Context ctxx) {
Log.d("ConnectedThread", "constructor ConnectedThread");
mContext = ctxx;
mmSocket = socket;
InputStream tmpIn = null;
OutputStream tmpOut = null;
temp = new ArrayList<Float>();
// Get the BluetoothSocket input and output streams
try {
tmpIn = socket.getInputStream();
tmpOut = socket.getOutputStream();
} catch (IOException e) {
Log.e("ConnectedThread", "it was trying create input and output sockets", e);
}
mmInStream = tmpIn;
mmOutStream = tmpOut;
}
public void run() {
Log.i("ConnectedThread", "run mConnectedThread");
byte[] buffer = new byte[1024];
/*int i = 0;
while(true)
{
Log.i("ConnectedThread", "sending int test value");
write(i++);
}*/
doBindService();
}
/**
* 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("ConnectedThread", "Exception during write", e);
}
}
public void write(int out) {
try {
mmOutStream.write(out);
} catch (IOException e) {
Log.e("ConnectedThread", "Exception during write", e);
}
}
public void cancel() {
try {
//mmOutStream.write(EXIT_CMD);
mmSocket.close();
} catch (IOException e) {
Log.e("ConnectedThread", "close() of connect socket failed", e);
}
}
///------------------------------
/**
* Handler of incoming messages from service.
*/
class IncomingHandler extends Handler {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case SensorMsgService.MSG_SET_VALUE:
temp = (ArrayList<Float>) msg.obj;
//mCallbackText.setText("Received from service: " + msg.arg1);
Log.d("Handle message from service", temp.get(0) + " " + temp.get(1) + " " + temp.get(2) + "\n");
break;
default:
super.handleMessage(msg);
}
}
}
/**
* Class for interacting with the main interface of the service.
*/
private ServiceConnection mConnection = new ServiceConnection() {
public void onServiceConnected(ComponentName className, IBinder service) {
// This is called when the connection with the service has been
// established, giving us the service object we can use to
// interact with the service. We are communicating with our
// service through an IDL interface, so get a client-side
// representation of that from the raw service object.
mService = new Messenger(service);
//mCallbackText.setText("Attached.");
// We want to monitor the service for as long as we are
// connected to it.
try {
Message msg = Message.obtain(null,
SensorMsgService.MSG_REGISTER_CLIENT);
msg.replyTo = mMessenger;
mService.send(msg);
// Give it some value as an example.
msg = Message.obtain(null, SensorMsgService.MSG_SET_VALUE, this
.hashCode(), 0);
mService.send(msg);
} catch (RemoteException e) {
// In this case the service has crashed before we could even
// do anything with it; we can count on soon being
// disconnected (and then reconnected if it can be restarted)
// so there is no need to do anything here.
}
// As part of the sample, tell the user what happened.
Toast.makeText(mContext, "Service connected",
Toast.LENGTH_SHORT).show();
}
public void onServiceDisconnected(ComponentName className) {
// This is called when the connection with the service has been
// unexpectedly disconnected -- that is, its process crashed.
mService = null;
//mCallbackText.setText("Disconnected.");
// As part of the sample, tell the user what happened.
Toast.makeText(mContext, "Service disconnedcted",
Toast.LENGTH_SHORT).show();
}
};
/**
* Target we publish for clients to send messages to IncomingHandler.
*/
final Messenger mMessenger = new Messenger(new IncomingHandler());
// do Bind
void doBindService() {
// Establish a connection with the service. We use an explicit
// class name because there is no reason to be able to let other
// applications replace our component.
mContext.bindService(new Intent(mContext, SensorMsgService.class),
mConnection, Context.BIND_AUTO_CREATE);
mIsBound = true;
Log.d("ConnectedThread", "doBindService");
}
void doUnbindService() {
if (mIsBound) {
// If we have received the service, and hence registered with
// it, then now is the time to unregister.
if (mService != null) {
try {
Message msg = Message.obtain(null,
SensorMsgService.MSG_UNREGISTER_CLIENT);
msg.replyTo = mMessenger;
mService.send(msg);
} catch (RemoteException e) {
// There is nothing special we need to do if the service
// has crashed.
}
}
// Detach our existing connection.
mContext.unbindService(mConnection);
mIsBound = false;
//mCallbackText.setText("Unbinding.");
}
}
}
问题是当我想运行这个帖子时：
04-04 01:36:26.853: W/dalvikvm(29341): threadid=12: thread exiting with uncaught exception (group=0x420372a0)
04-04 01:36:26.853: E/AndroidRuntime(29341): FATAL EXCEPTION: Thread-11596
04-04 01:36:26.853: E/AndroidRuntime(29341): java.lang.RuntimeException: Can't create handler inside thread that has not called Looper.prepare()
04-04 01:36:26.853: E/AndroidRuntime(29341): at android.os.Handler.<init> (Handler.java:121)
04-04 01:36:26.853: E/AndroidRuntime(29341): at com.nauka.bluetooth.ConnectedThread$IncomingHandler.<init>(ConnectedThread.java:127)
04-04 01:36:26.853: E/AndroidRuntime(29341): at com.nauka.bluetooth.ConnectedThread.<init>(ConnectedThread.java:200)
你能告诉我如何处理这个问题吗？ THX