Activity Class for MagnetometerDemo App on WIMM ONE

gistfile1.java

public class MagnetometerDemoActivity extends LauncherActivity implements SensorEventListener {
    public static final String TAG = MagnetometerDemoActivity.class.getSimpleName();

    /**
     * We could use Math.toDegrees(), but we can take away division from 
     * calculations by just multiplying by this static value instead.
     */
    public static float TO_DEGREES = (1 / (float) Math.PI) * 180;    

    /* 
     * If the magnetometer reports values over a certain value the user is
     * either near a strong magnet, we need to prompt the user to move away
     * or re-calibrate the device.  
     */
    private static final float MAGNETIC_INTERFERENCE_THRESHOLD = SensorManager.MAGNETIC_FIELD_EARTH_MAX * 2.5f;
    private static final float RECALIBRATION_THRESHOLD = MAGNETIC_INTERFERENCE_THRESHOLD * 4;    

    /* 
     * We will track the last time we displayed the Interference view and only 
     * show it again after this time interval.
     */    
    private static final int MS_BETWEEN_INTERFERENCE = 1000;
    
    private CompassView mCompassView;
    private TextView mTextView;

    private static SensorManager mSensorManager;	
    private Sensor mMagneticFieldSensor;
    private Sensor mAccelerometerSensor;
    private PowerManager.WakeLock mWakeLock;
	
    // Rotation matrix required for our Orientation calculations
    private float mRotationMatrix[] = new float[9];
    // Used to store device orientation about 3 axis.
    private float mOrientation[] = new float[3];
    
    private float[] mMagneticFieldVals;
    private float[] mAccelerationVals;
    private long mLastInterferenceTime;
    private boolean mRecalibrationNeeded;
    private boolean mShowCalibrationText = false;
    
    @Override
    public void onCreate(Bundle savedInstanceState) {
	super.onCreate(savedInstanceState); 
	setContentView(R.layout.main);

	/* 
	 * Obtain a wakelock so that we can prevent the watchface from obscuring 
	 * our activity while the user is reading the compass. 
	 */
	final PowerManager powerManager = (PowerManager)getSystemService(POWER_SERVICE); 
	mWakeLock = powerManager.newWakeLock(PowerManager.FULL_WAKE_LOCK, "MagnetometerDemoWakeLock");

        mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
	mAccelerometerSensor = mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
	mMagneticFieldSensor = mSensorManager.getDefaultSensor(Sensor.TYPE_MAGNETIC_FIELD);
	    
        mTextView = (TextView)findViewById(R.id.textView);
        mCompassView = (CompassView)findViewById(R.id.compassView);
	    
    }
    
    //Rest of the code goes here
}