프로페셔널 안드로이드 애플리케이션 개발 - 리토 마이어

요 책에 나와있는, 가속도센서를 이용한 속도계 구현 예제가, SensorListener에서 SensorEventListener로 바꿔줘야되잖아요?

그래서 어줍잖은 초보실력으로 이것저것 바꿔보았는데, 역시나 핸드폰에서는 속도는 커녕 아무반응이 없습니다.;;

전문가님들 도와주세요 ㅠㅠ  어느부분을 더 손봐야하는지 알려주시면 감사하겠습니다.

작성한 Java 파일 올립니다.

package kr.speespract;

import java.util.Date;
import java.util.Timer;
import java.util.TimerTask;

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 android.os.Handler;
import android.widget.TextView;

public class SpeedPract extends Activity implements SensorEventListener {

   Handler handler = new Handler();

   SensorManager sensorManager;
  TextView myTextView;

  float appliedAcceleration = 0;
  float currentAcceleration = 0;
  float velocity = 0;
  Date lastUpdate;    

  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    myTextView = (TextView)findViewById(R.id.myTextView);
    lastUpdate = new Date(System.currentTimeMillis());

    sensorManager = (SensorManager)getSystemService(Context.SENSOR_SERVICE);
    sensorManager.registerListener(this, sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), SensorManager.SENSOR_DELAY_FASTEST);

    Timer updateTimer = new Timer("velocityUpdate");
    updateTimer.scheduleAtFixedRate(new TimerTask() {
         public void run() {
           updateGUI();
         }
       }, 0, 1000);
  }

  private void updateGUI() {
    // Convert from meters per second to miles per hour.
    final double mph = (Math.round(100*velocity / 1.6 * 3.6))/100;

    // Update the GUI
    handler.post(new Runnable() {
       public void run() {
         myTextView.setText(String.valueOf(mph) + "mph");
       }
     });
  }

   private void updateVelocity() {
    // Calculate how long this acceleration has been applied.
    Date timeNow = new Date(System.currentTimeMillis());
    long timeDelta = timeNow.getTime()-lastUpdate.getTime();
    lastUpdate.setTime(timeNow.getTime());

    // Calculate the change in velocity at the 
    // current acceleration since the last update. 
    float deltaVelocity = appliedAcceleration * (timeDelta/1000);
    appliedAcceleration = currentAcceleration;

    // Add the velocity change to the current velocity.
    velocity += deltaVelocity;
  }

  private final SensorEventListener sensorEvent = new SensorEventListener() {

     double calibration = Double.NaN;
    
     public void onSensorChanged(SensorEvent event) {        
       double x = event.values[SensorManager.DATA_X];
       double y = event.values[SensorManager.DATA_Y];
       double z = event.values[SensorManager.DATA_Z];
       
       double a = Math.sqrt(Math.pow(x, 2) + Math.pow(y, 2) + Math.pow(z, 2)); 
       
       if (calibration == Double.NaN)
         calibration = a;
       else {
         updateVelocity();
         currentAcceleration = (float)a;
       }
     }

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

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

 @Override
 public void onSensorChanged(SensorEvent event) {
  // TODO Auto-generated method stub
  
 }

 public SensorEventListener getSensorEvent() {
  return sensorEvent;
 }
 }

*공지사항을 다 읽었습니다.