Question

I am using Motorola Xoom with WiFi for application development purpose.I have tried to implement code to create speedometer using accelerometer but the only problem I am facing is that JAVA compiler is deprecating “Sensorlistener”. I need some help to fix it. My using following codes for JAVA and .xml layout

JAVA

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

import android.app.Activity;
import android.content.Context;
import android.hardware.SensorListener;
import android.hardware.SensorManager;
import android.os.Bundle;
import android.os.Handler;
import android.widget.TextView;

public class Speedometer extends Activity {

  Handler handler = new Handler();

  SensorManager sensorManager;
    TextView myTextView;

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

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

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

      sensorManager = (SensorManager)getSystemService(Context.SENSOR_SERVICE);
      sensorManager.registerListener(sensorListener, SensorManager.SENSOR_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 SensorListener sensorListener = new SensorListener() {

    double calibration = Double.NaN;

    public void onSensorChanged(int sensor, float[] values) {        
      double x = values[SensorManager.DATA_X];
      double y = values[SensorManager.DATA_Y];
      double z = 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(int sensor, int accuracy) {}
  };
}

.XML

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:orientation="vertical"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent">
  <TextView android:id="@+id/myTextView"
    android:gravity="center"
    android:layout_width="fill_parent" 
    android:layout_height="fill_parent" 
    android:textStyle="bold" 
    android:textSize="40sp" 
    android:text="CENTER" 
    android:editable="false" 
    android:singleLine="true" 
    android:layout_margin="10px"/>
  />
</LinearLayout>

I will be grateful for helpful suggestions.

Answer 1

The documentation spells it out, just use SensorEventListener instead.