Question

我在我的MainActivity中实现了SensorEventListener，它运行得很好，我甚至可以说大部分时间。

但奇怪的是，有时它完全停止工作，我需要在每个方向上摇动它5-10秒，然后它神奇地重新开始。好像是手机长时间处于闲置/睡眠状态之后。

我确实在onResume / onPause上实现了注册/取消注册。

这是我的代码，主要来自stackoverflow：

SensorManager sensorManager;

private float accel; // acceleration apart from gravity
private float accelCurrent; // current acceleration including gravity
private float accelLast; // last acceleration including gravity
private static final float SHAKE_THRESHOLD = 12.f;


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    initSensor();
}


private void initSensor() {
    sensorManager = (SensorManager) getSystemService(SENSOR_SERVICE);
    registerSensor();
}

private void registerSensor() {
    HandlerThread handlerThread = new HandlerThread(HANDLER_THREAD_NAME_SENSOR);
    handlerThread.start();
    Handler handler = new Handler(handlerThread.getLooper());
    sensorManager.registerListener(this, sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), SensorManager.SENSOR_DELAY_NORMAL, handler);
    accel = 0.00f;
    accelCurrent = SensorManager.GRAVITY_EARTH;
    accelLast = SensorManager.GRAVITY_EARTH;
}

@Override
protected void onPause() {
    super.onPause();
    sensorManager.unregisterListener(this);
}

@Override
protected void onResume() {
    super.onResume();
    registerSensor();
}

@Override
public void onSensorChanged(SensorEvent event) {
    float x = event.values[0];
    float y = event.values[1];
    float z = event.values[2];
    accelLast = accelCurrent;
    accelCurrent = (float) Math.sqrt((double) (x*x + y*y + z*z));
    float delta = accelCurrent - accelLast;
    accel = accel * 0.9f + delta; // perform low-cut filter
    //Log.d(TAG, ">>> ALL shake accel = "+ accel);
    if (accel > SHAKE_THRESHOLD) {
        Log.d(TAG, "shake accel = "+ accel);
        runOnUiThread(new Runnable() {
            @Override
            public void run() {
                // Do stuffs in the UI
            }
        });

    }
}

@Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {
    // Nothing do to here
}

Answer 1

通过将传感器延迟更改为SensorManager.SENSOR_DELAY_FASTEST来修复; 注册现在看起来像：

// Global
private static final String HANDLER_THREAD_NAME_SENSOR = "sensorThread";

// ...Registration
HandlerThread handlerThread = new HandlerThread(HANDLER_THREAD_NAME_SENSOR);
handlerThread.start();
Handler handler = new Handler(handlerThread.getLooper());
mSensorManager.registerListener(this,
                    mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER),
                    SensorManager.SENSOR_DELAY_FASTEST,
                    handler);

SensorEventListener暂时无法正常工作

1 个答案: