我有AsyncTask,在doInBackground中我设置了一个timerTask,它实例化了下面发布的UpdateLogFile类。正如你在那堂课中看到的那样 我注册了一个传感器监听器,并在onCancelled和onPostExecute中取消注册,但问题是传感器lsitener始终注册 并且无法取消注册,因为即使我取消了AsyncTask,我仍然收到Log.w(TAG,CSubTag.msg(“onSensorChanged”));
请让我知道为什么会这样,以及如何正确注销。
码:
@Override
protected void onPostExecute(Void aVoid) {
super.onPostExecute(aVoid);
Log.w(TAG, CSubTag.msg("ATRx.onPostExecute"));
mSenMgr.unregisterListener(mSEL);
}
..
..
..
private class UpdateLogFile extends TimerTask {
private File mLogFile = null;
private long mStartTs;
private double mLng;
private double mLat;
private long mTs;
UpdateLogFile(File logFile, long startTs) {
this.mLogFile = logFile;
this.mStartTs = startTs;
mSenMgr = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
mSensAcc = mSenMgr.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
mSensMag = mSenMgr.getDefaultSensor(Sensor.TYPE_MAGNETIC_FIELD);
mSEL = new SensorEventListener() {
float[] mGravity;
float[] mGeomagnetic;
@Override
public void onSensorChanged(SensorEvent event) {
Log.w(TAG, CSubTag.msg("onSensorChanged"));
Sensor mySensor = event.sensor;
if (mySensor.getType() == Sensor.TYPE_ACCELEROMETER) {
mGravity = event.values;
}
if (mySensor.getType() == Sensor.TYPE_MAGNETIC_FIELD) {
mGeomagnetic = event.values;
}
if (mGravity != null && mGeomagnetic != null) {
float R[] = new float[9];
float I[] = new float[9];
boolean success = SensorManager.getRotationMatrix(R, I, mGravity, mGeomagnetic);
if (success) {
float orientation[] = new float[3];
SensorManager.getOrientation(R, orientation);
mAzimuth = orientation[0];
mPitch = orientation[1];
mRoll = orientation[2];
}
}
}
@Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {
}
};
mSenMgr.registerListener(mSEL, mSensAcc, SensorManager.SENSOR_DELAY_NORMAL);
mSenMgr.registerListener(mSEL, mSensMag, SensorManager.SENSOR_DELAY_NORMAL);
}
@Override
public void run() {
long endTs = TimeUtils.getTSSec();
this.mTs = endTs - this.mStartTs;
this.mLng = mGPSCtrl.getLng();
this.mLat = mGPSCtrl.getLat();
IOCtrl.writeLog(this.mLogFile, this.mTs, this.mLng, this.mLat, mAzimuth, mPitch, mRoll, mFMSMsg1, mFMSMsg2, mFMSMsg3, mFMSMsg4, mFMSMsg7, mFMSMsg8, mFMSMsg12);
Log.d(TAG, CSubTag.msg("UpdateTimer.run", "line: " + this.mLng + "," + this.mLat + "," + mAzimuth + "," + mPitch + "," + mRoll + "," + mFMSMsg1 + "," + mFMSMsg2 + "," + mFMSMsg3 + "," + mFMSMsg4 + "," + mFMSMsg7 + "," + mFMSMsg8 + "," + mFMSMsg12));
}
}
答案 0 :(得分:3)
在取消注册侦听器时,您是否检查过mSEL
是否为空?
如果你想听传感器,你应该创建一个Activity / Service / AsyncTask / ...来实现
android.hardware.SensorEventListener 界面。 (此page介绍了SensorEventListeners。)然后您可以随时取消注册侦听器(mSenMgr.unregisterListener(this)
)。
尝试以下方法:
public class CustomTask extends AsyncTask<SensorManager, Void, Void> implements SensorEventListener {
private SensorManager sensorManager;
@Override
public void onSensorChanged(SensorEvent event) { }
@Override
public void onAccuracyChanged(Sensor sensor, int accuracy) { }
@Override
protected Void doInBackground(SensorManager... params) {
sensorManager = params[0];
return null;
}
@Override
protected void onPostExecute(Void aVoid) {
super.onPostExecute(aVoid);
sensorManager.unregisterListener(this);
}
}
这是注册监听器的代码:
SensorManager mSenMgr = (SensorManager) getActivity().getSystemService(Context.SENSOR_SERVICE);
Sensor mSensAcc = mSenMgr.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
CustomTask task = new CustomTask();
task.doInBackground(mSenMgr);
mSenMgr.registerListener(task, mSensAcc, SensorManager.SENSOR_DELAY_NORMAL);