我创建了一个后台服务，即使应用程序被终止也可以使用。在服务中，我从传感器获取数据。但似乎我的服务在一秒钟内多次返回传感器值，导致我的应用程序被绞死。
这是我的服务：
public class StepCounterService extends Service {
private static final String LOG_TAG = "ForegroundService";
public static Boolean FLAG = false;
private SensorManager mSensorManager;
private StepDetector detector;
private PowerManager mPowerManager;
private WakeLock mWakeLock;
@Override
public IBinder onBind(Intent intent) {
// TODO Auto-generated method stub
return null;
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
/* mSensorManager = (SensorManager) this.getSystemService(SENSOR_SERVICE);
mSensorManager.registerListener(detector,
mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER),
SensorManager.SENSOR_DELAY_FASTEST);*/
Log.d("zzz", "start command");
return START_STICKY;
}
@Override
public void onCreate() {
// TODO Auto-generated method stub
super.onCreate();
new StepCountManager(this);
Log.d("zzz", "create");
FLAG = true;
Log.e("Service_Started", "");
detector = new StepDetector(this);
mSensorManager = (SensorManager) this.getSystemService(SENSOR_SERVICE);
mSensorManager.registerListener(detector,
mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER),
SensorManager.SENSOR_DELAY_FASTEST);
mPowerManager = (PowerManager) this
.getSystemService(Context.POWER_SERVICE);
mWakeLock = mPowerManager.newWakeLock(PowerManager.SCREEN_DIM_WAKE_LOCK
| PowerManager.ACQUIRE_CAUSES_WAKEUP, "S");
mWakeLock.acquire();
reloadSettings();
}
@Override
public void onDestroy() {
// TODO Auto-generated method stub
super.onDestroy();
FLAG = false;
if (detector != null) {
mSensorManager.unregisterListener(detector);
}
if (mWakeLock != null) {
mWakeLock.release();
}
Log.e("Service_destroyed", "");
}
public void reloadSettings() {
if (detector != null) {
detector.setSensitivity(
Float.valueOf("10")
);
}
}
@Override
public void onTaskRemoved(Intent rootIntent) {
super.onTaskRemoved(rootIntent);
Intent restartService = new Intent(getApplicationContext(),
this.getClass());
restartService.setPackage(getPackageName());
PendingIntent restartServicePI = PendingIntent.getService(
getApplicationContext(), 1, restartService,
PendingIntent.FLAG_ONE_SHOT);
//Restart the service once it has been killed android
// AlarmManager alarmService = (AlarmManager)getApplicationContext().getSystemService(Context.ALARM_SERVICE);
// alarmService.set(AlarmManager.ELAPSED_REALTIME, SystemClock.elapsedRealtime() +100, restartServicePI);
((AlarmManager) getSystemService(Context.ALARM_SERVICE))
.set(AlarmManager.RTC, System.currentTimeMillis() + 1000, PendingIntent
.getService(this, 3, new Intent(this, StepCounterService.class), 0));
}
}
这是我的类实现sensorEventListener：
public class StepDetector implements SensorEventListener {
public static UpdateStepCount mStepsUpdater;
public static int CURRENT_SETP = 0;
public static float SENSITIVITY = 0; //SENSITIVITY
private float mLastValues[] = new float[3 * 2];
private float mScale[] = new float[2];
private float mYOffset;
private static long end = 0;
private static long start = 0;
private float mLimit = 10;
private float mLastDirections[] = new float[3 * 2];
private float mLastExtremes[][] = { new float[3 * 2], new float[3 * 2] };
private float mLastDiff[] = new float[3 * 2];
private int mLastMatch = -1;
public StepDetector(Context context) {
// TODO Auto-generated constructor stub
super();
int h = 480;
mYOffset = h * 0.5f;
mScale[0] = -(h * 0.5f * (1.0f / (SensorManager.STANDARD_GRAVITY * 2)));
mScale[1] = -(h * 0.5f * (1.0f / (SensorManager.MAGNETIC_FIELD_EARTH_MAX)));
}
public void setSensitivity(float sensitivity) {
mLimit = sensitivity; // 1.97 2.96 4.44 6.66 10.00 15.00 22.50 33.75 50.62
}
@Override
public void onSensorChanged(SensorEvent event) {
Log.d("zzz", "Sensor changed");
Sensor sensor = event.sensor;
// Log.i(Constant.STEP_DETECTOR, "onSensorChanged");
synchronized (this) {
if (sensor.getType() == Sensor.TYPE_ORIENTATION) {
} else {
int j = (sensor.getType() == Sensor.TYPE_ACCELEROMETER) ? 1 : 0;
if (j == 1) {
float vSum = 0;
for (int i = 0; i < 3; i++) {
final float v = mYOffset + event.values[i] * mScale[j];
vSum += v;
}
int k = 0;
float v = vSum / 3;
float direction = (v > mLastValues[k] ? 1: (v < mLastValues[k] ? -1 : 0));
if (direction == -mLastDirections[k]) {
// Direction changed
int extType = (direction > 0 ? 0 : 1); // minimum or
// maximum?
mLastExtremes[extType][k] = mLastValues[k];
float diff = Math.abs(mLastExtremes[extType][k]- mLastExtremes[1 - extType][k]);
if (diff > mLimit) {
boolean isAlmostAsLargeAsPrevious = diff > (mLastDiff[k] * 2 / 3);
boolean isPreviousLargeEnough = mLastDiff[k] > (diff / 3);
boolean isNotContra = (mLastMatch != 1 - extType);
if (isAlmostAsLargeAsPrevious && isPreviousLargeEnough && isNotContra) {
end = System.currentTimeMillis();
if (end - start > 500) {
Log.i("Step_Detector", "CURRENT_SETP:"
+ CURRENT_SETP);
CURRENT_SETP++;
mLastMatch = extType;
start = end;
}
} else {
mLastMatch = -1;
}
}
mLastDiff[k] = diff;
}
mLastDirections[k] = direction;
mLastValues[k] = v;
}
}
}
Log.d("sensorSteps", String.valueOf(CURRENT_SETP));
new Handler().postDelayed(new Runnable() {
public void run() {
if(mStepsUpdater!=null){
mStepsUpdater.UpdateStepCount(CURRENT_SETP);
}
}
}, 1000);
}
@Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {
// TODO Auto-generated method stub
}
我希望我的服务能够在一秒内返回传感器数据，这样我就可以将数据存储在db中。有人能告诉我如何每秒获取传感器数据而不是一秒钟的倍数。