package anywheresoftware.b4a.student;

import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.util.FloatMath;

public class ShakeEventListener implements SensorEventListener {

    /*
     * The gForce that is necessary to register as shake.
     * Must be greater than 1G (one earth gravity unit).
     * You can install "G-Force", by Blake La Pierre
     * from the Google Play Store and run it to see how
     *  many G's it takes to register a shake
     */
    private static final float SHAKE_THRESHOLD_GRAVITY = 2.7F;
    private static int SHAKE_SLOP_TIME_MS = 500;
    private static final int SHAKE_COUNT_RESET_TIME_MS = 1000;

    private OnShakeListener mListener;
    private long mShakeTimestamp;
    private int mShakeCount;

    public void setOnShakeListener(OnShakeListener listener) {
        this.mListener = listener;
    }

    public interface OnShakeListener {
        public void onShake(int count);
    }

    @Override
    public void onAccuracyChanged(Sensor sensor, int accuracy) {
        // ignore
    }

    @Override
    public void onSensorChanged(SensorEvent event) {

        if (mListener != null) {
            float x = event.values[0];
            float y = event.values[1];
            float z = event.values[2];

            float gX = x / SensorManager.GRAVITY_EARTH;
            float gY = y / SensorManager.GRAVITY_EARTH;
            float gZ = z / SensorManager.GRAVITY_EARTH;

            // gForce will be close to 1 when there is no movement.
            float gForce = FloatMath.sqrt(gX * gX + gY * gY + gZ * gZ);

            if (gForce > SHAKE_THRESHOLD_GRAVITY) {
                final long now = System.currentTimeMillis();
                // ignore shake events too close to each other (500ms)
                if (mShakeTimestamp + getSHAKE_SLOP_TIME_MS() > now) {
                    return;
                }

                // reset the shake count after 3 seconds of no shakes
                if (mShakeTimestamp + SHAKE_COUNT_RESET_TIME_MS < now) {
                    mShakeCount = 0;
                }

                mShakeTimestamp = now;
                mShakeCount++;

                mListener.onShake(mShakeCount);
            }
        }
    }

    private long getSHAKE_SLOP_TIME_MS() {
        // TODO Auto-generated method stub
        return SHAKE_SLOP_TIME_MS;
    }

    public void setSHAKE_SLOP_TIME_MS(int sHAKE_SLOP_TIME_MS) {
        SHAKE_SLOP_TIME_MS = sHAKE_SLOP_TIME_MS;
    }   

}

你可能想试试开源tinybus。有了它，震动检测就像这样简单。

public class MainActivity extends Activity {

    private Bus mBus;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        ...

        // Create a bus and attach it to activity
        mBus = TinyBus.from(this).wire(new ShakeEventWire());
    }

    @Subscribe
    public void onShakeEvent(ShakeEvent event) {
        Toast.makeText(this, "Device has been shaken", 
                Toast.LENGTH_SHORT).show();
    }

    @Override
    protected void onStart() {
        super.onStart();
        mBus.register(this);
    }

    @Override
    protected void onStop() {
        mBus.unregister(this);
        super.onStop();
    }
}

它采用地震仪进行振动检测。

我已经尝试了几种实现，但我想分享一下我自己的实现。 它以g力为单位进行阈值计算。这让我们更容易理解发生了什么，同时也设置了一个好的阈值。

它只是记录G力的增加，如果超过阈值就触发侦听器。它不使用任何方向阈值，因为如果你只是想记录一个好的震动，你真的不需要这个。

当然，您需要在Activity中对这个侦听器进行标准的注册和un -注册。

此外，为了检查您需要的阈值，我推荐以下应用程序(我没有以任何方式连接到该应用程序)

    public class UmitoShakeEventListener implements SensorEventListener {

    /**
     * The gforce that is necessary to register as shake. (Must include 1G
     * gravity)
     */
    private final float shakeThresholdInGForce = 2.25F;

    private final float gravityEarth = SensorManager.GRAVITY_EARTH;

    private OnShakeListener listener;

    public void setOnShakeListener(OnShakeListener listener) {
        this.listener = listener;
    }

    public interface OnShakeListener {
        public void onShake();
    }

    @Override
    public void onAccuracyChanged(Sensor sensor, int accuracy) {
        // ignore

    }

    @Override
    public void onSensorChanged(SensorEvent event) {

        if (listener != null) {
            float x = event.values[0];
            float y = event.values[1];
            float z = event.values[2];

            float gX = x / gravityEarth;
            float gY = y / gravityEarth;
            float gZ = z / gravityEarth;

            //G-Force will be 1 when there is no movement. (gravity)
            float gForce = FloatMath.sqrt(gX * gX + gY * gY + gZ * gZ); 



            if (gForce > shakeThresholdInGForce) {
                listener.onShake();

            }
        }

    }

}

// Need to implement SensorListener
public class ShakeActivity extends Activity implements SensorListener {
// For shake motion detection.
private SensorManager sensorMgr;
private long lastUpdate = -1;
private float x, y, z;
private float last_x, last_y, last_z;
private static final int SHAKE_THRESHOLD = 800;

protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// start motion detection
sensorMgr = (SensorManager) getSystemService(SENSOR_SERVICE);
boolean accelSupported = sensorMgr.registerListener(this,
    SensorManager.SENSOR_ACCELEROMETER,
    SensorManager.SENSOR_DELAY_GAME);

if (!accelSupported) {
    // on accelerometer on this device
    sensorMgr.unregisterListener(this,
            SensorManager.SENSOR_ACCELEROMETER);
}
}

protected void onPause() {
if (sensorMgr != null) {
    sensorMgr.unregisterListener(this,
            SensorManager.SENSOR_ACCELEROMETER);
    sensorMgr = null;
    }
super.onPause();
}

public void onAccuracyChanged(int arg0, int arg1) {
// TODO Auto-generated method stub
}

public void onSensorChanged(int sensor, float[] values) {
if (sensor == SensorManager.SENSOR_ACCELEROMETER) {
    long curTime = System.currentTimeMillis();
    // only allow one update every 100ms.
    if ((curTime - lastUpdate)> 100) {
    long diffTime = (curTime - lastUpdate);
    lastUpdate = curTime;

    x = values[SensorManager.DATA_X];
    y = values[SensorManager.DATA_Y];
    z = values[SensorManager.DATA_Z];

    float speed = Math.abs(x+y+z - last_x - last_y - last_z)
                          / diffTime * 10000;
    if (speed > SHAKE_THRESHOLD) {
        // yes, this is a shake action! Do something about it!
    }
    last_x = x;
    last_y = y;
    last_z = z;
    }
}
}
}

您应该订阅SensorEventListener，并获取加速度计数据。 一旦你有了它，你应该监测在某个轴上加速度方向(符号)的突然变化。这将是一个很好的指示“摇动”移动的设备。

下面是一个示例代码。 把这些放到你的活动课上:

  /* put this into your activity class */
  private SensorManager mSensorManager;
  private float mAccel; // acceleration apart from gravity
  private float mAccelCurrent; // current acceleration including gravity
  private float mAccelLast; // last acceleration including gravity

  private final SensorEventListener mSensorListener = new SensorEventListener() {

    public void onSensorChanged(SensorEvent se) {
      float x = se.values[0];
      float y = se.values[1];
      float z = se.values[2];
      mAccelLast = mAccelCurrent;
      mAccelCurrent = (float) Math.sqrt((double) (x*x + y*y + z*z));
      float delta = mAccelCurrent - mAccelLast;
      mAccel = mAccel * 0.9f + delta; // perform low-cut filter
    }

    public void onAccuracyChanged(Sensor sensor, int accuracy) {
    }
  };

  @Override
  protected void onResume() {
    super.onResume();
    mSensorManager.registerListener(mSensorListener, mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), SensorManager.SENSOR_DELAY_NORMAL);
  }

  @Override
  protected void onPause() {
    mSensorManager.unregisterListener(mSensorListener);
    super.onPause();
  }

把这个添加到你的onCreate方法中:

    /* do this in onCreate */
    mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
    mSensorManager.registerListener(mSensorListener, mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), SensorManager.SENSOR_DELAY_NORMAL);
    mAccel = 0.00f;
    mAccelCurrent = SensorManager.GRAVITY_EARTH;
    mAccelLast = SensorManager.GRAVITY_EARTH;

然后你可以在你的应用程序中任何你想要的地方询问“mAccel”当前加速度，独立于轴，并从静态加速度(如重力)中清除。 大概是。如果没有移动，则为0，如果设备震动，则为>2。

根据评论-测试这一点:

if (mAccel > 12) {
    Toast toast = Toast.makeText(getApplicationContext(), "Device has shaken.", Toast.LENGTH_LONG);
    toast.show();
}

注:

The accelometer should be deactivated onPause and activated onResume to save resources (CPU, Battery). The code assumes we are on planet Earth ;-) and initializes the acceleration to earth gravity. Otherwise you would get a strong "shake" when the application starts and "hits" the ground from free-fall. However, the code gets used to the gravitation due to the low-cut filter and would work also on other planets or in free space, once it is initialized. (you never know how long your application will be in use...;-)