Develop Reference

Determine compass direction

I am browsing the internet trying to find something that would be usefull in my Android App.
I have my GPS location and several markers added to Google Map. When I turn around the location arrow is ponting wherever I am facing. My concern is if there is any way to determine on which marker I am pointing at? I have made a picture to clarify this.
I presume I can get compass bearing using getRotationMatrix() method, but how can I determine angle between location and the marker?

Checkout Compass class in this project: https://github.com/iutinvg/compass
I have used it succsesfully in this app: https://play.google.com/store/apps/details?id=com.gps.build
Regards.
UPDATE:
After reading your question again, i have realized that I did not give you enough details for "pointing to marker" part. Please check full class below. To calculate pointing direction, us startBearing and stopBearing methods.
Note that bearing degrees are changing with device rotation in BringMeBack class with setBearingDegrees method. Thats is not what you need, so you just have to remove locationManager and to put static bearing coordinate. And call that method only once.
Extended compass class:
package com.gps.bitlab;
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.support.v4.app.FragmentActivity;
import android.util.Log;
import android.view.animation.Animation;
import android.view.animation.RotateAnimation;
import android.widget.ImageView;
import com.gps.bitlab.fragment.MessageDialogFragment;
import com.gps.bitlab.util.Utility;
public class Compass implements SensorEventListener {
private static final String TAG = "Compass";
private SensorManager sensorManager;
private Sensor gsensor;
private Sensor msensor;
private float[] mGravity = new float[3];
private float[] mGeomagnetic = new float[3];
private float azimuth = 0f;
private float currectAzimuth = 0;
private boolean bearing = false;
private float bearingDegrees = -1;
// compass arrow to rotate
public ImageView arrowView = null;
FragmentActivity activity;
public Compass(FragmentActivity activity) {
this.activity = activity;
sensorManager = (SensorManager) activity.getApplicationContext()
.getSystemService(Context.SENSOR_SERVICE);
gsensor = sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
msensor = sensorManager.getDefaultSensor(Sensor.TYPE_MAGNETIC_FIELD);
}
public void start() {
boolean deviceSensorCompatible = true;
if(!sensorManager.registerListener(this, gsensor, SensorManager.SENSOR_DELAY_GAME))
deviceSensorCompatible = false;
if(!sensorManager.registerListener(this, msensor, SensorManager.SENSOR_DELAY_GAME))
deviceSensorCompatible = false;
if(!deviceSensorCompatible) {
Utility.ShowMessage(activity, activity.getString(R.string.erroroccured), activity.getString(R.string.deviceIncompatible), 1);
stop();
}
}
public void startBearing()
{
bearing = true;
start();
}
public void setBearingDegrees(float bearingDegrees)
{
this.bearingDegrees = bearingDegrees;
}
public void stop() {
sensorManager.unregisterListener(this);
}
public void stopBearing()
{
bearing = false;
stop();
}
private void adjustArrow() {
if (arrowView == null) {
Log.i(TAG, "arrow view is not set");
return;
}
Animation an = new RotateAnimation(-currectAzimuth, -azimuth,
Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF,
0.5f);
currectAzimuth = azimuth;
an.setDuration(250);
an.setRepeatCount(0);
an.setFillAfter(true);
arrowView.startAnimation(an);
}
#Override
public void onSensorChanged(SensorEvent event) {
final float alpha = 0.97f;
synchronized (this) {
if (event.sensor.getType() == Sensor.TYPE_ACCELEROMETER) {
mGravity[0] = alpha * mGravity[0] + (1 - alpha)
* event.values[0];
mGravity[1] = alpha * mGravity[1] + (1 - alpha)
* event.values[1];
mGravity[2] = alpha * mGravity[2] + (1 - alpha)
* event.values[2];
// mGravity = event.values;
// Log.e(TAG, Float.toString(mGravity[0]));
}
if (event.sensor.getType() == Sensor.TYPE_MAGNETIC_FIELD) {
// mGeomagnetic = event.values;
mGeomagnetic[0] = alpha * mGeomagnetic[0] + (1 - alpha)
* event.values[0];
mGeomagnetic[1] = alpha * mGeomagnetic[1] + (1 - alpha)
* event.values[1];
mGeomagnetic[2] = alpha * mGeomagnetic[2] + (1 - alpha)
* event.values[2];
// Log.e(TAG, Float.toString(event.values[0]));
}
float R[] = new float[9];
float I[] = new float[9];
boolean success = SensorManager.getRotationMatrix(R, I, mGravity,
mGeomagnetic);
if (success) {
float orientation[] = new float[3];
SensorManager.getOrientation(R, orientation);
// Log.d(TAG, "azimuth (rad): " + azimuth);
azimuth = (float) Math.toDegrees(orientation[0]); // orientation
azimuth = (azimuth + 360) % 360;
if(bearing) {
if(bearingDegrees != -1) {
azimuth -= bearingDegrees;
adjustArrow();
}
}
else
adjustArrow();
// Log.d(TAG, "azimuth (deg): " + azimuth);
}
}
}
#Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {
}
}
Class that use pointing to location functionality:
package com.gps.bitlab;
import android.content.Intent;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.MenuItem;
import android.view.View;
import android.view.WindowManager;
import android.widget.FrameLayout;
import android.widget.ImageView;
import android.widget.LinearLayout;
import com.gps.bitlab.R;
import com.gps.bitlab.fragment.OnDialogClickListener;
import com.gps.bitlab.util.Utility;
public class BringMeBack extends ActionBarActivity implements LocationListener, OnDialogClickListener {
LocationManager locMng;
Location location;
double lat;
double lon;
double alt;
String name;
Compass compass;
FrameLayout bearingParentLayout;
LinearLayout BaseLayout;
ImageView arrow;
boolean layoutReplaced = false;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Utility.SetLocalization(this);
setContentView(R.layout.activity_bring_me_back);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
getActionBar().setDisplayHomeAsUpEnabled(true);
bearingParentLayout = (FrameLayout)findViewById(R.id.bearingParentLayout);
BaseLayout = Utility.GetLoadingView(getLayoutInflater(), getString(R.string.waitingForLocation));
if(savedInstanceState != null)
{
lat = savedInstanceState.getDouble("lat");
lon = savedInstanceState.getDouble("lon");
alt = savedInstanceState.getDouble("alt");
name = savedInstanceState.getString("name");
}
else {
lat = getIntent().getExtras().getDouble("lat");
lon = getIntent().getExtras().getDouble("lon");
alt = getIntent().getExtras().getDouble("alt");
name = getIntent().getExtras().getString("name");
}
if(name != null && !name.equals(""))
getActionBar().setTitle(name);
locMng = (LocationManager)getSystemService(LOCATION_SERVICE);
location = new Location(LocationManager.GPS_PROVIDER);
location.setLongitude(lon);
location.setLatitude(lat);
location.setAltitude(alt);
arrow = (ImageView)findViewById(R.id.bearingArrow);
compass = new Compass(this);
compass.arrowView = arrow;
arrow.setVisibility(View.GONE);
bearingParentLayout.addView(BaseLayout);
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == android.R.id.home) {
BringMeBack.this.finish();
}
return super.onOptionsItemSelected(item);
}
#Override
protected void onPause() {
super.onPause();
compass.stopBearing();
locMng.removeUpdates(this);
}
#Override
protected void onResume() {
super.onResume();
compass.startBearing();
RequestLocationUpdates();
}
#Override
public void onLocationChanged(Location currentLocation) {
float bearing = currentLocation.bearingTo(location);
Log.d("Location bearing", String.valueOf(bearing));
compass.setBearingDegrees(bearing);
if(!layoutReplaced) {
bearingParentLayout.removeView(BaseLayout);
arrow.setVisibility(View.VISIBLE);
layoutReplaced = true;
}
}
#Override
public void onStatusChanged(String s, int i, Bundle bundle) {
}
#Override
public void onProviderEnabled(String s) {
Log.d("GPS", "Service enabled");
RequestLocationUpdates();
}
#Override
public void onProviderDisabled(String s) {
locMng.removeUpdates(this);
Utility.ShowMessage(BringMeBack.this, getString(R.string.locationServiceDisabledMessage), getString(R.string.locationServiceDisabled), 0);
}
#Override
public void OnPositiveClick(int key, Object... args) {
startActivity(new Intent(android.provider.Settings.ACTION_LOCATION_SOURCE_SETTINGS));
}
#Override
public void OnNegativeClick(int key, Object... args) {
}
private void RequestLocationUpdates()
{
if(!locMng.isProviderEnabled(LocationManager.GPS_PROVIDER))
Utility.ShowMessage(BringMeBack.this, getString(R.string.locationServiceDisabledMessage), getString(R.string.locationServiceDisabled), 0);
else
locMng.requestLocationUpdates(LocationManager.GPS_PROVIDER, 500, 0, this);
}
}

One class cannot extend two classes

Hey :) I have a code of a ball that using the motion sensor and I want to make my app count time and when you lose, save this time for a record, so I did it, but my problem is, I can't extend my fragment layout, here is my full code:
package com.example.theball;
import java.util.Timer;
import java.util.TimerTask;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.app.Fragment;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;
import android.content.pm.ActivityInfo;
import android.graphics.Canvas;
import android.graphics.Point;
import android.graphics.drawable.ShapeDrawable;
import android.graphics.drawable.shapes.OvalShape;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.os.Bundle;
import android.view.Display;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.TextView;
#SuppressLint("NewApi") public class MainActivity extends Activity implements SensorEventListener {
private SensorManager sensorManager;
private Sensor accelerometer;
#SuppressWarnings("unused")
private long lastUpdate;
AnimatedView animatedView = null;
ShapeDrawable mDrawable = new ShapeDrawable();
public static int x;
public static int y;
public static final int width = 50;
public static final int height = 50;
public boolean firstDraw = true;
private int screen_width;
private int screen_height;
private int sensorX;
private Timer t;
private int TimeCounter = 0;
private int sensorY;
private static int score = 0;
private static SharedPreferences prefs;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
setRequestedOrientation (ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
sensorManager = (SensorManager) getSystemService(SENSOR_SERVICE);
accelerometer = sensorManager
.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
lastUpdate = System.currentTimeMillis();
animatedView = new AnimatedView(this);
setContentView(animatedView);
t=new Timer();
t.scheduleAtFixedRate(new TimerTask() {
public void run() {
runOnUiThread(new Runnable() {
public void run() {
TimeCounter++;
}
});
}
}, 0, 1000);
}
public static class MainFragment extends Fragment {
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.activity_main, container, false);
TextView highscore_int = (TextView)v.findViewById(R.id.highscore_int );
score = prefs.getInt("key", 0);
highscore_int.setText("Highscore:" + score +" seconds.");
return v;
}
}
#Override
protected void onResume() {
super.onResume();
sensorManager.registerListener(this, accelerometer,
SensorManager.SENSOR_DELAY_GAME);
}
#Override
protected void onPause() {
super.onPause();
sensorManager.unregisterListener(this);
}
#Override
public void onAccuracyChanged(Sensor arg0, int arg1) {
// TODO Auto-generated method stub
}
#Override
public void onSensorChanged(SensorEvent event) {
// TODO Auto-generated method stub
if (event.sensor.getType() == Sensor.TYPE_ACCELEROMETER) {
sensorY = (int) event.values[1];
sensorX = (int) event.values[0];
x -= sensorX*3;
y += sensorY*3;
if(x <= 0 || x >= screen_width || y <= 0 || y >= screen_height) {
SharedPreferences prefs = this.getSharedPreferences("myPrefsKey", Context.MODE_PRIVATE);
int oldScore = prefs.getInt("key", 0);
if( TimeCounter > oldScore ){
Editor edit = prefs.edit();
edit.putInt("key", TimeCounter);
edit.commit(); }
Intent myIntent = new Intent(this, YouLost.class);
startActivity(myIntent);
}
}
}
public class AnimatedView extends ImageView {
Display display = getWindowManager().getDefaultDisplay();
Point size = new Point();
static final int width = 50;
static final int height = 50;
#SuppressLint("NewApi")
public AnimatedView(Context context) {
super(context);
// TODO Auto-generated constructor stub
display.getSize(size);
screen_width = size.x;
screen_height = size.y;
mDrawable = new ShapeDrawable(new OvalShape());
mDrawable.getPaint().setColor(0xffffAC23);
mDrawable.setBounds(0, 0, screen_width, screen_height);
}
#Override
protected void onDraw(Canvas canvas) {
mDrawable.setBounds(x, y, x + width, y + height);
if(firstDraw) {
x = screen_width / 2;
y = screen_height / 2;
firstDraw = false;
}
mDrawable.draw(canvas);
invalidate();
}
}
}
XML FILE:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView
android:id="#+id/highscore_int"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginLeft="0dp"
android:layout_marginTop="0dp"
android:layout_weight="0.14"
android:text="12312312"
android:textColor="#android:color/black"
android:textSize="40sp" />
</LinearLayout>
I can't see the highscore_int on my device, only at the eclipse xml file grahpic layout.

You have defined MainActivity twice. Rename the second one to e.g. MainFragment (or something else) and you should be fine.
But I would also recommend to move the Fragment to a different file as well.

Android Tilting-Mind blowing

So here is my code if someone be kind enough to help out.
I want the orientation values to be displayed but all I get is 0.0 0.0 0.0 so I dont know whats going on I dont think its my phone becasue it fairly modern (HTC One V)
package ple.x75;
import android.app.Activity;
import android.content.Context;
import android.content.pm.ActivityInfo;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.os.Bundle;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Button;
import android.view.View;
public class MainActivity extends Activity
{
private ImageView img;
private SensorManager mSensorManager;
private float[] mAccelerometerReading;
private float[] mMagneticFieldReading;
private float[] mRotationMatrix = new float[16];
private float[] mRemapedRotationMatrix = new float[16];
private float[] mOrientation = new float[3];
// Register the event listener and sensor type.
public void setListners(SensorManager sensorManager, SensorEventListener mEventListener)
{
sensorManager.registerListener(mEventListener, sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER),
SensorManager.SENSOR_DELAY_NORMAL);
sensorManager.registerListener(mEventListener, sensorManager.getDefaultSensor(Sensor.TYPE_MAGNETIC_FIELD),
SensorManager.SENSOR_DELAY_NORMAL);
}
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
SensorManager sensorManager = (SensorManager) this.getSystemService(SENSOR_SERVICE);
final Button btn_valider = (Button) findViewById(R.id.button);
final TextView txt1 = (TextView) findViewById(R.id.textView);
final SensorEventListener mEventListener = new SensorEventListener() {
public void onAccuracyChanged(Sensor sensor, int accuracy) {
}
public void onSensorChanged(SensorEvent event) {
switch (event.sensor.getType()) {
case Sensor.TYPE_ACCELEROMETER:
mAccelerometerReading = event.values.clone();
break;
case Sensor.TYPE_MAGNETIC_FIELD:
mMagneticFieldReading = event.values.clone();
break;
}
if(mAccelerometerReading != null && mMagneticFieldReading != null &&
SensorManager.getRotationMatrix(mRotationMatrix, null, mAccelerometerReading, mMagneticFieldReading))
{
SensorManager.remapCoordinateSystem(mRotationMatrix,
SensorManager.AXIS_Y, SensorManager.AXIS_MINUS_X, mRemapedRotationMatrix);
SensorManager.getOrientation(mRemapedRotationMatrix, mOrientation);
}
};
};
setListners(sensorManager, mEventListener);
btn_valider.setOnClickListener(new View.OnClickListener()
{
public void onClick(View view)
{
if(mOrientation != null)
{
final CharSequence test;
test="Results: "+mOrientation[0]+" "+mOrientation[1]+" "+mOrientation[2];
txt1.setText(test);
}
else{
final CharSequence test;
test="Results: Apparently Nothing...";
txt1.setText(test);
}
}
});
}
}

How to get more than two color when i shake my handheld device.My App is on sensor

Hi my app is on sensors and I am not able to find any other color if i shake it.I have provided only two colors in if else loop. But if in want to add some more colors then what should i add. What is the solution.Please help me in this problem.
package com.sensortestactivity;
import android.app.Activity;
import android.graphics.Color;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.os.Bundle;
import android.view.View;
import android.view.Window;
import android.view.WindowManager;
import android.widget.Toast;
public class SensorTestActivity extends Activity implements SensorEventListener {
private SensorManager sensorManager;
private Boolean color = false;
private View view;
private long lastUpdate;
// -- CALLED WHEN THE ACTIVITY IS FIRST CREATED --//
#Override
public void onCreate(Bundle savedInstanceState) {
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
view = findViewById(R.id.textView);
view.setBackgroundColor(Color.GREEN);
sensorManager = (SensorManager) getSystemService(SENSOR_SERVICE);
sensorManager.registerListener(this,
sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER),
SensorManager.SENSOR_DELAY_NORMAL);
lastUpdate = System.currentTimeMillis();
}
#Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {
}
#Override
public void onSensorChanged(SensorEvent event) {
if (event.sensor.getType() == Sensor.TYPE_ACCELEROMETER) {
getAccelerometer(event);
}
}
private void getAccelerometer(SensorEvent event) {
float[] values = event.values;
// -- MOVEMENT --
float x = values[0];
float y = values[1];
float z = values[2];
float accelerationSquareRoot = (x * x + y * y + z * z)
/ (SensorManager.GRAVITY_EARTH * SensorManager.GRAVITY_EARTH);
long actualTime = System.currentTimeMillis();
if (accelerationSquareRoot >= 2) {
if (actualTime - lastUpdate < 200) {
return;
}
lastUpdate = actualTime;
Toast.makeText(this, "DEVICE WAS SHUFFELED", Toast.LENGTH_SHORT)
.show();
if (color) {
view.setBackgroundColor(Color.GREEN);
} else {
view.setBackgroundColor(Color.RED);
}
color = !color;
}
}
#Override
protected void onPause() {
super.onPause();
sensorManager.unregisterListener(this);
}
#Override
protected void onResume() {
super.onResume();
// -- REGISTER THIS CLASS AS A LISTENER FOR THE ORIENTATION AND
// ACCELEROMETER SENSORS --
sensorManager.registerListener(this,
sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER),
SensorManager.SENSOR_DELAY_NORMAL);
}
}

you may use
view.setBackgroundColor(HEXVALUE);
The hexvalue is used like this: 0xAARRGGBB
AA = alpha channel
RR = red channel
GG = green channel
BB = blue channel
A valid color would be: 0xFFFF0000 which will create red
Another valid color: 0xFFF0F0F0
for hex numbers you should take a look at wikipedia. http://en.wikipedia.org/wiki/Hexadecimal
You can randomly set the color using a random number generator.
Math.random() * 17
This will give you integer values starting with 0 and ending at 16. You just need to calc those to hex:
0 = 0
1 = 1
2 = 2
...
9 = 9
10 = A
11 = B
...
16 = F

Accelerometer code

I am working with accelerometer for android, I do not understand why the three axis for them which I have assigned to mSensorX, mSensorY and mSensorZ are labelled as unused when I have used them in the onSensorChange, could someone please help me understand this.
package com.example.imageaccel;
import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.os.Bundle;
import android.widget.TextView;
public class ImageAccelActivity extends Activity implements SensorEventListener {
/** Called when the activity is first created. */
TextView x, y, z;
private float mSensorX;
private float mSensorY;
private float mSensorZ;
private Bitmap car;
private SensorManager sm = null;
// Bitmap car1;
// float x1, y1, z1, sensorX, sensorY, sensorZ;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
x = (TextView)findViewById(R.id.x_axis);
y = (TextView)findViewById(R.id.y_axis);
z = (TextView)findViewById(R.id.z_axis);
SensorManager sm = (SensorManager)getSystemService(Context.SENSOR_SERVICE);
if (sm.getSensorList(Sensor.TYPE_ACCELEROMETER).size() !=0){
Sensor s = sm.getSensorList(Sensor.TYPE_ACCELEROMETER).get(0);
sm.registerListener(this, s, SensorManager.SENSOR_DELAY_NORMAL);
}
}
#Override
protected void onResume() {
// TODO Auto-generated method stub
super.onResume();
sm.registerListener(this, sm.getDefaultSensor(Sensor.TYPE_ACCELEROMETER),SensorManager.SENSOR_DELAY_NORMAL);
}
#Override
protected void onPause() {
// TODO Auto-generated method stub
super.onPause();
sm.unregisterListener(this);
super.onPause();
}
#Override
public void onAccuracyChanged(Sensor arg0, int arg1) {
// TODO Auto-generated method stub
}
#Override
public void onSensorChanged(SensorEvent ev) {
// TODO Auto-generated method stub
if(ev.sensor.getType()==Sensor.TYPE_ACCELEROMETER){
mSensorX = ev.values[0];
mSensorY = ev.values[1];
mSensorZ = ev.values[2];
}
}
protected void onDraw(Canvas canvas) {
/*
* draw the background
*/
canvas.drawBitmap(car, 0, 0, null);
}
}

You're setting them to a value but that's only half the story. The complaint is most likely that you're never using them after that. It's similar to the C code:
int main (void) {
int a = 1;
return 0;
}
While that compiles and runs fine, you do get a warning (using gcc -Wall) that:
warning: unused variable 'a'
Quick way to check this theory, put a:
System.out.println (mSensorX + "," + mSensorY + "," + mSensorZ);
(or some other sort of use) following the setting and see if the warning disappears.

I think there is a warning because of the if statement there..In some cases they won't be used and hence the warning..That's my opinion:)