震动事件侦听器

Posted 2021-02-23

Shake event listener

package com.xs2theworld.apptown.hardware;
 
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
 
/**
 * Listener that detects shake gesture.
 */
public class ShakeEventListener implements SensorEventListener {
 
	/** Minimum movement force to consider. */
	private static final int MIN_FORCE = 10;
 
	/**
	 * Minimum times in a shake gesture that the direction of movement needs to
	 * change.
	 */
	private static final int MIN_DIRECTION_CHANGE = 3;
 
	/** Maximum pause between movements. */
	private static final int MAX_PAUSE_BETHWEEN_DIRECTION_CHANGE = 200;
 
	/** Maximum allowed time for shake gesture. */
	private static final int MAX_TOTAL_DURATION_OF_SHAKE = 400;
 
	/** Time when the gesture started. */
	private long mFirstDirectionChangeTime = 0;
 
	/** Time when the last movement started. */
	private long mLastDirectionChangeTime;
 
	/** How many movements are considered so far. */
	private int mDirectionChangeCount = 0;
 
	/** The last x position. */
	private float lastX = 0;
 
	/** The last y position. */
	private float lastY = 0;
 
	/** The last z position. */
	private float lastZ = 0;
 
	/** OnShakeListener that is called when shake is detected. */
	private OnShakeListener mShakeListener;
 
	/**
	 * Interface for shake gesture.
	 */
	public interface OnShakeListener {
 
		/**
		 * Called when shake gesture is detected.
		 */
		void onShake();
	}
 
	public void setOnShakeListener(OnShakeListener listener) {
		mShakeListener = listener;
	}
 
	@Override
	public void onSensorChanged(SensorEvent se) {
		// get sensor data
		float x = se.values[SensorManager.DATA_X];
		float y = se.values[SensorManager.DATA_Y];
		float z = se.values[SensorManager.DATA_Z];
 
		// calculate movement
		float totalMovement = Math.abs(x + y + z - lastX - lastY - lastZ);
 
		if (totalMovement > MIN_FORCE) {
 
			// get time
			long now = System.currentTimeMillis();
 
			// store first movement time
			if (mFirstDirectionChangeTime == 0) {
				mFirstDirectionChangeTime = now;
				mLastDirectionChangeTime = now;
			}
 
			// check if the last movement was not long ago
			long lastChangeWasAgo = now - mLastDirectionChangeTime;
			if (lastChangeWasAgo < MAX_PAUSE_BETHWEEN_DIRECTION_CHANGE) {
 
				// store movement data
				mLastDirectionChangeTime = now;
				mDirectionChangeCount++;
 
				// store last sensor data
				lastX = x;
				lastY = y;
				lastZ = z;
 
				// check how many movements are so far
				if (mDirectionChangeCount >= MIN_DIRECTION_CHANGE) {
 
					// check total duration
					long totalDuration = now - mFirstDirectionChangeTime;
					if (totalDuration < MAX_TOTAL_DURATION_OF_SHAKE) {
						mShakeListener.onShake();
						resetShakeParameters();
					}
				}
 
			} else {
				resetShakeParameters();
			}
		}
	}
 
	/**
	 * Resets the shake parameters to their default values.
	 */
	private void resetShakeParameters() {
		mFirstDirectionChangeTime = 0;
		mDirectionChangeCount = 0;
		mLastDirectionChangeTime = 0;
		lastX = 0;
		lastY = 0;
		lastZ = 0;
	}
 
	@Override
	public void onAccuracyChanged(Sensor sensor, int accuracy) {
	}
 
}
 
In our activity:
 
 private SensorManager mSensorManager;
 
 private ShakeEventListener mSensorListener;
 
in our onCreate():
 
mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
    mSensorListener = new ShakeEventListener();   
 
    mSensorListener.setOnShakeListener(new ShakeEventListener.OnShakeListener() {
 
      public void onShake() {
        Toast.makeText(KPBActivityImpl.this, "Shake!", Toast.LENGTH_SHORT).show();
      }
    });
 
Then:
 
@Override
  protected void onResume() {
    super.onResume();
    mSensorManager.registerListener(mSensorListener,
        mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER),
        SensorManager.SENSOR_DELAY_UI);
  }
 
  @Override
  protected void onPause() {
    mSensorManager.unregisterListener(mSensorListener);
    super.onStop();
  }