I'm trying to make a compass that points at a specific Longitude/Latitude, but I don't know how this is made, so I'll appreciate any help :)
This is the compass. What do I've to add/change so that I can decide the Longitude/Latitude?
public class MainActivity extends Activity implements SensorEventListener {
private ImageView mPointer;
private SensorManager mSensorManager;
private Sensor mAccelerometer;
private Sensor mMagnetometer;
private float[] mLastAccelerometer = new float[3];
private float[] mLastMagnetometer = new float[3];
private boolean mLastAccelerometerSet = false;
private boolean mLastMagnetometerSet = false;
private float[] mR = new float[9];
private float[] mOrientation = new float[3];
private float mCurrentDegree = 0f;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mSensorManager = (SensorManager)getSystemService(SENSOR_SERVICE);
mAccelerometer = mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
mMagnetometer = mSensorManager.getDefaultSensor(Sensor.TYPE_MAGNETIC_FIELD);
mPointer = (ImageView) findViewById(R.id.pointer);
}
protected void onResume() {
super.onResume();
mSensorManager.registerListener(this, mAccelerometer, SensorManager.SENSOR_DELAY_GAME);
mSensorManager.registerListener(this, mMagnetometer, SensorManager.SENSOR_DELAY_GAME);
}
protected void onPause() {
super.onPause();
mSensorManager.unregisterListener(this, mAccelerometer);
mSensorManager.unregisterListener(this, mMagnetometer);
}
@Override
public void onSensorChanged(SensorEvent event) {
if (event.sensor == mAccelerometer) {
System.arraycopy(event.values, 0, mLastAccelerometer, 0, event.values.length);
mLastAccelerometerSet = true;
} else if (event.sensor == mMagnetometer) {
System.arraycopy(event.values, 0, mLastMagnetometer, 0, event.values.length);
mLastMagnetometerSet = true;
}
if (mLastAccelerometerSet && mLastMagnetometerSet) {
SensorManager.getRotationMatrix(mR, null, mLastAccelerometer, mLastMagnetometer);
SensorManager.getOrientation(mR, mOrientation);
float azimuthInRadians = mOrientation[0];
float azimuthInDegress = (float)(Math.toDegrees(azimuthInRadians)+360)%360;
RotateAnimation ra = new RotateAnimation(
mCurrentDegree,
-azimuthInDegress,
Animation.RELATIVE_TO_SELF, 0.5f,
Animation.RELATIVE_TO_SELF,
0.5f);
ra.setDuration(250);
ra.setFillAfter(true);
mPointer.startAnimation(ra);
mCurrentDegree = -azimuthInDegress;
}
}
@Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {
// TODO Auto-generated method stub
}
}
Maybe it's a little unclear. Let's say that I'm outside and I want to know the direction of a specific place. This app should help me finding the direction
