Sensor（GYROSCOPE）

package com.example.sensor01;

import java.util.List;

import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.widget.TextView;

public class MainActivity extends Activity implements SensorEventListener{
    
    private static final float NS2S = 1.0f / 1000000000.0f;
    private float timestamp;
    private SensorManager mSensorManager;
    private TextView textview;
    private float angle2 = 0,angle0 = 0,angle1 = 0;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        textview = (TextView) findViewById(R.id.content);
                
        mSensorManager = (SensorManager) getSystemService(SENSOR_SERVICE);

        Sensor sensor  = mSensorManager.getDefaultSensor(Sensor.TYPE_GYROSCOPE);

        mSensorManager.registerListener(this, sensor, SensorManager.SENSOR_DELAY_NORMAL);

    }

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

    @Override
    public void onSensorChanged(SensorEvent event) {
        
        float[] values = new float[3];
        
        
        if(0 != timestamp){
            
            final float dT = (event.timestamp - timestamp) * NS2S;
            
            if (event.sensor.getType() == Sensor.TYPE_GYROSCOPE){
                //三个方向的角速度
                values = event.values;
            }
            
            //三个方向转过的弧度
            angle0 += values[0] * dT;
            angle1 += values[1] * dT;
            angle2 += values[2] * dT;
            
            //三个方向将弧度转换为角度，即 角度=弧度除以π再乘以180 弧度=角度乘以π后再除以180
            float anglex = (float) Math.toDegrees(angle0);//前后垂直翻转的角度（相对于初始位置，即第一次取值）
            float angley = (float) Math.toDegrees(angle1);//左右翻转的角度（相对于初始位置，即第一次取值）
            float anglez = (float) Math.toDegrees(angle2);//左右摇摆的角度（相对于初始位置，即第一次取值）
            
            textview.setText(String.valueOf(anglex) + "   " 
            + String.valueOf(angley) + "  " + String.valueOf(anglez));    
        }
        
        timestamp = event.timestamp;
    }
}