turning phone

package com.huawei.voice.activity;
import android.app.Activity;
import android.content.Context;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.os.Bundle;

import com.huawei.voice.R;
import com.huawei.voice.util.Parameters;
import com.huawei.voice.util.ToastDeal;

/**
*
* 手机翻转事件处理  待测试
*
* @author  mickey_hou
* @version  1.0, 2012-5-17
* @since  Tiantian
*/
public class TurningDealActivity extends Activity implements SensorEventListener
{
    private SensorManager sensorManager;
   
    private ToastDeal deal = new ToastDeal();
   
    private long mLastUpdateTime;
   
    //private float mLastX, mLastY, mLastZ; 
   
    private Context myContext;
   
    public int shakeThreshold = 1500;
   
    @Override
    public void onCreate(Bundle bundle)
    {
        super.onCreate(bundle);
        setContentView(R.layout.main);
        myContext = TurningDealActivity.this;
        sensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
    }
   
    @Override
    protected void onResume()
    {
        super.onResume();
        sensorManager.registerListener(this,sensorManager.getDefaultSensor(
                    Sensor.TYPE_ACCELEROMETER),//TYPE_ACCELEROMETER  传感器类型 ：加速度
                    SensorManager.SENSOR_DELAY_NORMAL);
    }
   
    @Override
    protected void onStop()
    {
        sensorManager.unregisterListener(this);
        super.onStop();
    }
   
    public void onAccuracyChanged(Sensor sensor, int accuracy)
    {
    }
   
    public void onSensorChanged(SensorEvent event)
    {
        long currentTime = System.currentTimeMillis();
        long diffTime = currentTime - mLastUpdateTime;
        if (diffTime < Parameters.UPDATE_INTERVAL)
        {
            return;
        }
        this.mLastUpdateTime = currentTime;
       
        /*
         * 旋转角度测试
         */
        float[] values = event.values;
        float ax = values[0];
        float ay = values[1];

        double g = Math.sqrt(ax * ax + ay * ay);
        double cos = ay / g;
        if (cos > 1) {
            cos = 1;
        } else if (cos < -1) {
            cos = -1;
        }
        double rad = Math.acos(cos);
        if (ax < 0) {
            rad = 2 * Math.PI - rad;
        }

        int uiRot = getWindowManager().getDefaultDisplay().getRotation();
        double uiRad = Math.PI / 2 * uiRot;
        rad -= uiRad;
       
        /**
         * 当加速度的差值大于指定的阈值，认为这是一个摇晃 
         */
        if (rad >= 90 || rad < -90)
        {
            deal.showToast(myContext, "旋转角度为："+rad);
        }
    }
}