如何用android检测摇动事件？

Question

如何用android检测震动事件？如何检测摇动方向？

我想在发生抖动时更改图像视图中的图像.

Answer 1

从代码的角度来看,您需要实现SensorListener:

public class ShakeActivity extends Activity implements SensorListener

您需要获取SensorManager:

sensorMgr = (SensorManager) getSystemService(SENSOR_SERVICE);

并使用所需的标志注册此传感器:

sensorMgr.registerListener(this,
SensorManager.SENSOR_ACCELEROMETER,
SensorManager.SENSOR_DELAY_GAME);

在你的onSensorChange()方法中,你可以确定它是否是一个震动:

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) {
        Log.d("sensor", "shake detected w/ speed: " + speed);
        Toast.makeText(this, "shake detected w/ speed: " + speed, Toast.LENGTH_SHORT).show();
      }
      last_x = x;
      last_y = y;
      last_z = z;
    }
  }
}

震动阈值定义为:

private static final int SHAKE_THRESHOLD = 800;

还有一些其他方法来检测摇动.看看这个链接.(如果该链接不起作用或链接已死,请查看此Web存档.).

看看这个示例为android shake detect listener.

注意: SensorListener已弃用.我们可以SensorEventListener改用.以下是使用SensorEventListener的快速示例.

谢谢.

Answer 2

谷歌帮了很多忙.

/* The following code was written by Matthew Wiggins
 * and is released under the APACHE 2.0 license
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 */
package com.hlidskialf.android.hardware;

import android.hardware.SensorListener;
import android.hardware.SensorManager;
import android.content.Context;
import java.lang.UnsupportedOperationException;

public class ShakeListener implements SensorListener 
{
  private static final int FORCE_THRESHOLD = 350;
  private static final int TIME_THRESHOLD = 100;
  private static final int SHAKE_TIMEOUT = 500;
  private static final int SHAKE_DURATION = 1000;
  private static final int SHAKE_COUNT = 3;

  private SensorManager mSensorMgr;
  private float mLastX=-1.0f, mLastY=-1.0f, mLastZ=-1.0f;
  private long mLastTime;
  private OnShakeListener mShakeListener;
  private Context mContext;
  private int mShakeCount = 0;
  private long mLastShake;
  private long mLastForce;

  public interface OnShakeListener
  {
    public void onShake();
  }

  public ShakeListener(Context context) 
  { 
    mContext = context;
    resume();
  }

  public void setOnShakeListener(OnShakeListener listener)
  {
    mShakeListener = listener;
  }

  public void resume() {
    mSensorMgr = (SensorManager)mContext.getSystemService(Context.SENSOR_SERVICE);
    if (mSensorMgr == null) {
      throw new UnsupportedOperationException("Sensors not supported");
    }
    boolean supported = mSensorMgr.registerListener(this, SensorManager.SENSOR_ACCELEROMETER, SensorManager.SENSOR_DELAY_GAME);
    if (!supported) {
      mSensorMgr.unregisterListener(this, SensorManager.SENSOR_ACCELEROMETER);
      throw new UnsupportedOperationException("Accelerometer not supported");
    }
  }

  public void pause() {
    if (mSensorMgr != null) {
      mSensorMgr.unregisterListener(this, SensorManager.SENSOR_ACCELEROMETER);
      mSensorMgr = null;
    }
  }

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

  public void onSensorChanged(int sensor, float[] values) 
  {
    if (sensor != SensorManager.SENSOR_ACCELEROMETER) return;
    long now = System.currentTimeMillis();

    if ((now - mLastForce) > SHAKE_TIMEOUT) {
      mShakeCount = 0;
    }

    if ((now - mLastTime) > TIME_THRESHOLD) {
      long diff = now - mLastTime;
      float speed = Math.abs(values[SensorManager.DATA_X] + values[SensorManager.DATA_Y] + values[SensorManager.DATA_Z] - mLastX - mLastY - mLastZ) / diff * 10000;
      if (speed > FORCE_THRESHOLD) {
        if ((++mShakeCount >= SHAKE_COUNT) && (now - mLastShake > SHAKE_DURATION)) {
          mLastShake = now;
          mShakeCount = 0;
          if (mShakeListener != null) { 
            mShakeListener.onShake(); 
          }
        }
        mLastForce = now;
      }
      mLastTime = now;
      mLastX = values[SensorManager.DATA_X];
      mLastY = values[SensorManager.DATA_Y];
      mLastZ = values[SensorManager.DATA_Z];
    }
  }

}

Answer 3

您还可以使用代码示例查看JakeWharton库:https://github.com/square/seismic

Answer 4

这个问题已经有很多解决方案,但我想发布一个(1)不使用API​​ 3中描述的库,(2)正确计算加速度的大小,(3)正确应用震动事件之间的超时.这是一个解决方案:

// variables for shake detection
private static final float SHAKE_THRESHOLD = 3.25f; // m/S**2
private static final int MIN_TIME_BETWEEN_SHAKES_MILLISECS = 1000;
private long mLastShakeTime;
private SensorManager mSensorMgr;

要初始化计时器:

// Get a sensor manager to listen for shakes
mSensorMgr = (SensorManager) getSystemService(SENSOR_SERVICE);

// Listen for shakes
Sensor accelerometer = mSensorMgr.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
if (accelerometer != null) {
    mSensorMgr.registerListener(this, accelerometer, SensorManager.SENSOR_DELAY_NORMAL);
}

SensorEventListener 覆盖的方法:

@Override
public void onSensorChanged(SensorEvent event) {
    if (event.sensor.getType() == Sensor.TYPE_ACCELEROMETER) {
        long curTime = System.currentTimeMillis();
        if ((curTime - mLastShakeTime) > MIN_TIME_BETWEEN_SHAKES_MILLISECS) {

            float x = event.values[0];
            float y = event.values[1];
            float z = event.values[2];

            double acceleration = Math.sqrt(Math.pow(x, 2) +
                    Math.pow(y, 2) +
                    Math.pow(z, 2)) - SensorManager.GRAVITY_EARTH;
            Log.d(APP_NAME, "Acceleration is " + acceleration + "m/s^2");

            if (acceleration > SHAKE_THRESHOLD) {
                mLastShakeTime = curTime;
                Log.d(APP_NAME, "Shake, Rattle, and Roll");
            }
        }
    }
}

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

当你们都完成了

// Stop listening for shakes
mSensorMgr.unregisterListener(this);

Answer 5

由于不推荐使用SensorListener，因此请使用以下代码：

/* 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();
}

然后：

/* 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;

完整细节的问题可以在这里找到：

Android：我想动摇它

Answer 6

这是为了Kotlin和使用SensorEventListener

创建新班级 ShakeDetector

class ShakeDetector : SensorEventListener {
    private var mListener: OnShakeListener? = null
    private var mShakeTimestamp: Long = 0
    private var mShakeCount = 0
    fun setOnShakeListener(listener: OnShakeListener?) {
        mListener = listener
    }

    interface OnShakeListener {
        fun onShake(count: Int)
    }

    override fun onAccuracyChanged(
        sensor: Sensor,
        accuracy: Int
    ) { // ignore
    }

    override fun onSensorChanged(event: SensorEvent) {
        if (mListener != null) {
            val x = event.values[0]
            val y = event.values[1]
            val z = event.values[2]
            val gX = x / SensorManager.GRAVITY_EARTH
            val gY = y / SensorManager.GRAVITY_EARTH
            val gZ = z / SensorManager.GRAVITY_EARTH
            // gForce will be close to 1 when there is no movement.
            val gForce: Float = sqrt(gX * gX + gY * gY + gZ * gZ)
            if (gForce > SHAKE_THRESHOLD_GRAVITY) {
                val now = System.currentTimeMillis()
                // ignore shake events too close to each other (500ms)
                if (mShakeTimestamp + SHAKE_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)
            }
        }
    }

    companion object {
        /*
     * 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 const val SHAKE_THRESHOLD_GRAVITY = 2.7f
        private const val SHAKE_SLOP_TIME_MS = 500
        private const val SHAKE_COUNT_RESET_TIME_MS = 3000
    }
}

您的主要活动

class MainActivity : AppCompatActivity() {

    // The following are used for the shake detection
    private var mSensorManager: SensorManager? = null
    private var mAccelerometer: Sensor? = null
    private var mShakeDetector: ShakeDetector? = null

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        initSensor()
    }
    override fun onResume() {
        super.onResume()
        // Add the following line to register the Session Manager Listener onResume
        mSensorManager!!.registerListener(
            mShakeDetector,
            mAccelerometer,
            SensorManager.SENSOR_DELAY_UI
        )
    }

    override fun onPause() { // Add the following line to unregister the Sensor Manager onPause
        mSensorManager!!.unregisterListener(mShakeDetector)
        super.onPause()
    }

    private fun initSensor() {
        // ShakeDetector initialization
        // ShakeDetector initialization
        mSensorManager = getSystemService(SENSOR_SERVICE) as SensorManager
        mAccelerometer = mSensorManager!!.getDefaultSensor(Sensor.TYPE_ACCELEROMETER)
        mShakeDetector = ShakeDetector()
        mShakeDetector!!.setOnShakeListener(object : OnShakeListener {
            override fun onShake(count: Int) { /*
                 * The following method, "handleShakeEvent(count):" is a stub //
                 * method you would use to setup whatever you want done once the
                 * device has been shook.
                 */
                Toast.makeText(this@MainActivity, count.toString(), Toast.LENGTH_SHORT).show()
            }
        })
    }
}

最后将此代码添加到清单以确保手机具有加速度计

<uses-feature android:name="android.hardware.sensor.accelerometer" android:required="true" />