Android–Encryption Made Easy

Hi,

I am giving you following class that you can embed in your code to encrypt and decrypt. You just need to put a PASSWORD to call its init( ) method.

import java.io.ByteArrayInputStream;

import java.io.ByteArrayOutputStream;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileNotFoundException;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import java.util.Arrays;

import javax.crypto.Cipher;

import javax.crypto.CipherInputStream;

import javax.crypto.CipherOutputStream;

import javax.crypto.SecretKey;

import javax.crypto.SecretKeyFactory;

import javax.crypto.spec.PBEKeySpec;

import javax.crypto.spec.PBEParameterSpec;

public class Encryption {

    // related links http://stackoverflow.com/questions/2256774/android-secretkeyfactory-problems-implementation-not-found

    // http://download.oracle.com/javase/6/docs/technotes/guides/security/SunProviders.html

    // PBEWithMD5AndDES

    private static final String INSTANCE = "PBEWithSHA256And256BitAES-CBC-BC";

    private static final String TAG = "Encryption";

    private static final int SALT_LENGTH     = 10;

    private static final int SALT_ITERATIONS = 10;

    private static SecretKey secretKey;

    public static CipherOutputStream encryptionWrap(OutputStream os) {

        try {

            final byte salt[] = new byte[SALT_LENGTH];

            new java.security.SecureRandom().nextBytes(salt); // @TEMP

            os.write(salt);

            PBEParameterSpec pbeParamSpec = new PBEParameterSpec(salt, SALT_ITERATIONS);

            Cipher c = Cipher.getInstance(INSTANCE);

            c.init(Cipher.ENCRYPT_MODE, secretKey, pbeParamSpec);

            return new CipherOutputStream(os, c);

        } catch (Exception e) {

            OpenFeintInternal.log(TAG, e.getMessage());

        }

        return null;

    }

    public static CipherInputStream decryptionWrap(InputStream is) {

        try {

            final byte salt[] = new byte[SALT_LENGTH];

            if (is.read(salt) != SALT_LENGTH) throw new Exception("Couldn't read entire salt");

            PBEParameterSpec pbeParamSpec = new PBEParameterSpec(salt, SALT_ITERATIONS);

            Cipher c = Cipher.getInstance(INSTANCE);

            c.init(Cipher.DECRYPT_MODE, secretKey, pbeParamSpec);

            return new CipherInputStream(is, c);

        } catch (Exception e) {

            OpenFeintInternal.log(TAG, e.getMessage());

        }

        return null;

    }

    /*

     * if init return false, then this platform does not support

     * secure data store. then can't not use ofx

     */

    public static boolean init(String password) {

        try {

            PBEKeySpec pbeKeySpec = new PBEKeySpec(password.toCharArray());

            SecretKeyFactory keyFac = SecretKeyFactory.getInstance(INSTANCE);

            secretKey = keyFac.generateSecret(pbeKeySpec);

            // try to make an encrypter and decrypter to see if it works.

            byte testString[] = INSTANCE.getBytes(); // just write the name of the cipher we're using

            ByteArrayOutputStream baos = new ByteArrayOutputStream();

            CipherOutputStream cos = encryptionWrap(baos);

            cos.write(testString);

            cos.close();

            final byte[] encryptedContents = baos.toByteArray();

            if (encryptedContents.length == 0) throw new Exception();

            CipherInputStream cis = decryptionWrap(new ByteArrayInputStream(encryptedContents));

            byte decryptedContents[] = Util.toByteArray(cis);

            if (!Arrays.equals(decryptedContents, testString)) throw new Exception();

        } catch (Exception e) {

            secretKey = null;

            return false;

        }

        return true;

    }

    public static boolean initialized() {

        return secretKey != null;

    }

    public static InputStream decrypt(File file) throws FileNotFoundException {

        return decryptionWrap(new FileInputStream(file));

    }

    public static byte[] decryptFile(String path) throws FileNotFoundException, IOException {

        return Util.toByteArray(decrypt(new File(path)));

    }

    public static byte[] decrypt(byte input[]) {

        try {

            return Util.toByteArray(decryptionWrap(new ByteArrayInputStream(input)));

        } catch (Exception e) {

            return null;

        }

    }

    public static boolean encrypt(byte[] in, String path) {

        try {

            OutputStream os = encrypt(path);

            os.write(in);

            os.close();

            return true;

        } catch (Exception e) {

            // @TODO cleanup?

        }

        return false;

    }

    public static OutputStream encrypt(String path) throws FileNotFoundException {

        return encryptionWrap(new FileOutputStream(new File(path)));

    }

    public static byte[] encrypt(byte input[]) {

        try {

            ByteArrayOutputStream baos = new ByteArrayOutputStream();

            final CipherOutputStream enc = encryptionWrap(baos);

            enc.write(input);

            enc.close();

            return baos.toByteArray();

        } catch (Exception e) {

            return null;

        }

    }

}

Usage

if (!Encryption.initialized()) {
            Encryption.init(“Password”);
        }

Encryption.encryptionWrap(oos);

InputStream inn = Encryption.decryptionWrap(is);

Tags:

android, java, encryption, secret key factory problems solved,

Detecting App Installations alternative to IMEI

public class Installation {

    private static String sID = null;

    private static final String INSTALLATION = "INSTALLATION";

    public synchronized static String getIdentifier(Context context) {

        if (sID == null) {  

            File installation = new File(context.getFilesDir(), INSTALLATION);

            try {

                if (!installation.exists())

                    writeInstallationFile(installation);

                sID = readInstallationFile(installation);

            } catch (Exception e) {

                throw new RuntimeException(e);

            }

        }

        return sID;

    }

    private static String readInstallationFile(File installation) throws IOException {

        RandomAccessFile f = new RandomAccessFile(installation, "r");//read only mode

        byte[] bytes = new byte[(int) f.length()];

        f.readFully(bytes);        

        f.close();

        return new String(bytes);

    }

    private static void writeInstallationFile(File installation) throws IOException {

        FileOutputStream out = new FileOutputStream(installation);

        String id = UUID.randomUUID().toString();

        out.write(id.getBytes());

        out.close();

    }

}

If you are not giving support before Froyo then you can use ANDROID_ID

ANDROID_ID

More specifically, Settings.Secure.ANDROID_ID. This is a 64-bit quantity that is generated and stored when the device first boots. It is reset when the device is wiped.

ANDROID_ID seems a good choice for a unique device identifier. There are downsides: First, it is not 100% reliable on releases of Android prior to 2.2 (“Froyo”). Also, there has been at least one widely-observed bug in a popular handset from a major manufacturer, where every instance has the same ANDROID_ID.

 

 

POST URL: http://android-developers.blogspot.com/2011/03/identifying-app-installations.html

 

tags: android, unique, identifier, alternative, IMEI, android_id, android id

AndEngine Menu Scrolling Example

AndEngine Menu Scroll Example

//VERSION # 1

package dk.dionysus.hjarl;

import java.util.ArrayList;

import java.util.List;

import org.anddev.andengine.engine.Engine;

import org.anddev.andengine.engine.camera.Camera;

import org.anddev.andengine.engine.camera.hud.HUD;

import org.anddev.andengine.engine.options.EngineOptions;

import org.anddev.andengine.engine.options.EngineOptions.ScreenOrientation;

import org.anddev.andengine.engine.options.resolutionpolicy.FillResolutionPolicy;

import org.anddev.andengine.entity.primitive.Rectangle;

import org.anddev.andengine.entity.scene.Scene;

import org.anddev.andengine.entity.scene.Scene.IOnSceneTouchListener;

import org.anddev.andengine.entity.scene.background.ColorBackground;

import org.anddev.andengine.entity.sprite.Sprite;

import org.anddev.andengine.entity.util.FPSLogger;

import org.anddev.andengine.input.touch.TouchEvent;

import org.anddev.andengine.input.touch.detector.ClickDetector;

import org.anddev.andengine.input.touch.detector.ClickDetector.IClickDetectorListener;

import org.anddev.andengine.input.touch.detector.ScrollDetector;

import org.anddev.andengine.input.touch.detector.ScrollDetector.IScrollDetectorListener;

import org.anddev.andengine.input.touch.detector.SurfaceScrollDetector;

import org.anddev.andengine.opengl.font.Font;

import org.anddev.andengine.opengl.font.FontFactory;

import org.anddev.andengine.opengl.texture.TextureOptions;

import org.anddev.andengine.opengl.texture.atlas.bitmap.BitmapTextureAtlas;

import org.anddev.andengine.opengl.texture.atlas.bitmap.BitmapTextureAtlasTextureRegionFactory;

import org.anddev.andengine.opengl.texture.region.TextureRegion;

import org.anddev.andengine.ui.activity.BaseGameActivity;

import android.app.AlertDialog;

import android.content.DialogInterface;

import android.content.Intent;

import android.graphics.Color;

import android.view.KeyEvent;

import android.widget.Toast;

/**

 * 

 * @author Knoll Florian

 * @email myfknoll@gmail.com

 * @since 28.02.2012

 * @author Kasper Olesen

 * @website http://dionysus.dk/devstuff

 *

 */

public class ScrollMenu extends BaseGameActivity implements IScrollDetectorListener, IOnSceneTouchListener, IClickDetectorListener {

        // ===========================================================

        // Constants

        // ===========================================================

        protected static int CAMERA_WIDTH = 480;

        protected static int CAMERA_HEIGHT = 320;

        protected static int FONT_SIZE = 28;

        protected static int PADDING = 50;

        protected static int MENUITEMS = 7;

        // ===========================================================

        // Fields

        // ===========================================================

        private Scene mScene;

        private Camera mCamera;

        private Font mFont; 

        private BitmapTextureAtlas mFontTexture;     

        private BitmapTextureAtlas mMenuTextureAtlas;        

        private TextureRegion mMenuLeftTextureRegion;

        private TextureRegion mMenuRightTextureRegion;

        private BitmapTextureAtlas BackgroundTexture;

        private TextureRegion BackgroundTextureRegion;

        private Sprite background;

        private BitmapTextureAtlas TitleTexture;

        private TextureRegion TitleTextureRegion;

        private Sprite title;

        HUD hud = new HUD();

        private Sprite menuleft;

        private Sprite menuright;

        // Scrolling

        private SurfaceScrollDetector mScrollDetector;

        private ClickDetector mClickDetector;

        private float mMinX = 0;

        private float mMaxX = 0;

        private float mCurrentX = 0;

        private int iItemClicked = -1;

        private Rectangle scrollBar;        

        private List<TextureRegion> columns = new ArrayList<TextureRegion>();

        // ===========================================================

        // Constructors

        // ===========================================================

        // ===========================================================

        // Getter & Setter

        // ===========================================================

        // ===========================================================

        // Methods for/from SuperClass/Interfaces

        // ===========================================================

        @Override

        public void onLoadResources() {

                // Paths

                FontFactory.setAssetBasePath("font/");

                BitmapTextureAtlasTextureRegionFactory.setAssetBasePath("gfx/");

                // Font

                this.mFontTexture = new BitmapTextureAtlas(256, 256);

                this.mFont = FontFactory.createFromAsset(this.mFontTexture, this, "DIRTYDOZ.TTF", FONT_SIZE, true, Color.RED);

                this.mEngine.getTextureManager().loadTextures(this.mFontTexture);

                this.mEngine.getFontManager().loadFonts(this.mFont);

                this.BackgroundTexture = new BitmapTextureAtlas(1024, 1024, TextureOptions.REPEATING_BILINEAR_PREMULTIPLYALPHA);

                this.BackgroundTextureRegion = BitmapTextureAtlasTextureRegionFactory.createFromAsset(this.BackgroundTexture, this, "baggrund.jpg", 0, 0);

                this.TitleTexture = new BitmapTextureAtlas(512, 512, TextureOptions.REPEATING_BILINEAR_PREMULTIPLYALPHA);

                this.TitleTextureRegion = BitmapTextureAtlasTextureRegionFactory.createFromAsset(this.TitleTexture, this, "menu/title.png", 0, 0);

                //Images for the menu

                for (int i = 0; i < MENUITEMS; i++) {                

                    BitmapTextureAtlas mMenuBitmapTextureAtlas = new BitmapTextureAtlas(256,256, TextureOptions.BILINEAR_PREMULTIPLYALPHA);

                    TextureRegion mMenuTextureRegion = BitmapTextureAtlasTextureRegionFactory.createFromAsset(mMenuBitmapTextureAtlas, this, "menu/menu"+i+".png", 0, 0);

                    this.mEngine.getTextureManager().loadTexture(mMenuBitmapTextureAtlas);

                    columns.add(mMenuTextureRegion);

                }

                //Textures for menu arrows

                this.mMenuTextureAtlas = new BitmapTextureAtlas(128,128, TextureOptions.BILINEAR_PREMULTIPLYALPHA);

                this.mMenuLeftTextureRegion = BitmapTextureAtlasTextureRegionFactory.createFromAsset(mMenuTextureAtlas, this, "menu/menu_left.png", 0, 0);

                this.mMenuRightTextureRegion = BitmapTextureAtlasTextureRegionFactory.createFromAsset(mMenuTextureAtlas, this, "menu/menu_right.png",64, 0);

                this.mEngine.getTextureManager().loadTextures(mMenuTextureAtlas, BackgroundTexture, TitleTexture);

        }

        @Override

        public Engine onLoadEngine() {

                this.mCamera = new Camera(0, 0, CAMERA_WIDTH, CAMERA_HEIGHT);

                final EngineOptions engineOptions = new EngineOptions(true, ScreenOrientation.LANDSCAPE, new FillResolutionPolicy(), this.mCamera);

                engineOptions.getTouchOptions().setRunOnUpdateThread(true);

                final Engine engine = new Engine(engineOptions);

                return engine;

        }

        @Override

        public Scene onLoadScene() {

                this.mEngine.registerUpdateHandler(new FPSLogger());

                this.mScene = new Scene();

                this.mScene.setBackground(new ColorBackground(0, 0, 0));

                int x = (CAMERA_WIDTH - this.BackgroundTextureRegion.getWidth()) / 2;

                int y = (CAMERA_HEIGHT - this.BackgroundTextureRegion.getHeight()) / 2;

                background = new Sprite(x, y, this.BackgroundTextureRegion);

                background.setScale(1.25f);

                mScene.attachChild(background);

                x = (CAMERA_WIDTH - this.TitleTextureRegion.getWidth()) / 2;

                y = (this.TitleTextureRegion.getHeight() / 2);

                title = new Sprite(x, y, this.TitleTextureRegion);

                title.setScale(0.8f);

                mScene.attachChild(title);

                this.mScrollDetector = new SurfaceScrollDetector(this);

                this.mClickDetector = new ClickDetector(this);

                this.mScene.setOnSceneTouchListener(this);

                this.mScene.setTouchAreaBindingEnabled(true);

                this.mScene.setOnSceneTouchListenerBindingEnabled(true);

                CreateMenuBoxes();

                return this.mScene;

        }

        @Override

        public boolean onSceneTouchEvent(final Scene pScene, final TouchEvent pSceneTouchEvent) {

                this.mClickDetector.onTouchEvent(pSceneTouchEvent);

                this.mScrollDetector.onTouchEvent(pSceneTouchEvent);

                return true;

        }

        @Override

        public void onScroll(final ScrollDetector pScollDetector, final TouchEvent pTouchEvent, final float pDistanceX, final float pDistanceY) {

                //Disable the menu arrows left and right (15px padding)

                if(mCamera.getMinX()<=15)

                     menuleft.setVisible(false);

                 else

                     menuleft.setVisible(true);

                 if(mCamera.getMinX()>mMaxX-15)

                     menuright.setVisible(false);

                 else

                     menuright.setVisible(true);

                //Return if ends are reached

                if ( ((mCurrentX - pDistanceX) < mMinX)  ){                    

                    return;

                }else if((mCurrentX - pDistanceX) > mMaxX){

                    return;

                }

                //Center camera to the current point

                this.mCamera.offsetCenter(-pDistanceX,0 );

                mCurrentX -= pDistanceX;

                //Set the scrollbar with the camera

                float tempX =mCamera.getCenterX()-CAMERA_WIDTH/2;

                // add the % part to the position

                tempX+= (tempX/(mMaxX+CAMERA_WIDTH))*CAMERA_WIDTH;      

                //set the position

                scrollBar.setPosition(tempX, scrollBar.getY());

                //set the arrows for left and right

                menuright.setPosition(mCamera.getCenterX()+CAMERA_WIDTH/2-menuright.getWidth(),menuright.getY());

                menuleft.setPosition(mCamera.getCenterX()-CAMERA_WIDTH/2,menuleft.getY());

                background.setPosition(mCamera.getCenterX()-background.getWidth() / 2,background.getY());

                title.setPosition(mCamera.getCenterX()-title.getWidth() / 2,title.getY());

                //Because Camera can have negativ X values, so set to 0

                if(this.mCamera.getMinX()<0){

                    this.mCamera.offsetCenter(0,0 );

                    mCurrentX=0;

                }

        }

        @Override

        public void onClick(ClickDetector pClickDetector, TouchEvent pTouchEvent) {

                loadLevel(iItemClicked);

        };

        // ===========================================================

        // Methods

        // ===========================================================

        private void CreateMenuBoxes() {

             int spriteX = PADDING;

             int spriteY = PADDING;

             //current item counter

             int iItem = 1;

             for (int x = 0; x < columns.size(); x++) {

                 //On Touch, save the clicked item in case it's a click and not a scroll.

                 final int itemToLoad = iItem;

                 Sprite sprite = new Sprite(spriteX,spriteY + CAMERA_HEIGHT / 4 - 15,columns.get(x)){

                     public boolean onAreaTouched(final TouchEvent pSceneTouchEvent, final float pTouchAreaLocalX, final float pTouchAreaLocalY) {

                         iItemClicked = itemToLoad;

                         return false;

                     }                     

                 };                 

                 iItem++;

                 this.mScene.attachChild(sprite);                 

                 this.mScene.registerTouchArea(sprite);                 

                 spriteX += 20 + PADDING+sprite.getWidth();

            }

             mMaxX = spriteX - CAMERA_WIDTH;

             //set the size of the scrollbar

             float scrollbarsize = CAMERA_WIDTH/((mMaxX+CAMERA_WIDTH)/CAMERA_WIDTH);

             scrollBar = new Rectangle(0,CAMERA_HEIGHT-20,scrollbarsize, 20);

             scrollBar.setColor(1,0,0);

             this.mScene.attachChild(scrollBar);

             menuleft = new Sprite(0,CAMERA_HEIGHT/2-mMenuLeftTextureRegion.getHeight()/2,mMenuLeftTextureRegion);

             menuright = new Sprite(CAMERA_WIDTH-mMenuRightTextureRegion.getWidth(),CAMERA_HEIGHT/2-mMenuRightTextureRegion.getHeight()/2,mMenuRightTextureRegion);

             this.mScene.attachChild(menuright);

             menuleft.setVisible(false);

             this.mScene.attachChild(menuleft);

        }

        @Override

        public void onLoadComplete() {

        }

        //Here is where you call the item load.

        private void loadLevel(final int iLevel) {

                if (iLevel != -1) {

                        runOnUiThread(new Runnable() {

                                @Override

                                public void run() {

                                        Toast.makeText(ScrollMenu.this, "Load Item" + String.valueOf(iLevel), Toast.LENGTH_SHORT).show();

                                        if (iLevel == 1) {

                                            Intent game = new Intent(ScrollMenu.this, HjarlGameActivity.class); // When clicked, run HjarlGameActivity

                                            startActivity(game); // runs the game intent, which targets the HjarlGameActivity

                                        }

                                        if (iLevel == 2) {

                                            Intent game = new Intent(ScrollMenu.this, RacerGameActivity.class); // When clicked, run RacerGameActivity

                                            startActivity(game); // runs the game intent, which targets the RacerGameActivity

                                        }

                                        if (iLevel == 3) {

                                            Intent control = new Intent(ScrollMenu.this, OSControlSetup.class);

                                            startActivity(control);

                                        }

                                        if (iLevel == 4) {

                                            Intent game = new Intent(ScrollMenu.this, OptionsActivity.class);

                                            startActivity(game);

                                        }

                                        if (iLevel == 5) {

                                            Intent help = new Intent(ScrollMenu.this, HelpActivity.class);

                                            startActivity(help);

                                        }

                                        if (iLevel == 6) {

                                            Intent help = new Intent(ScrollMenu.this, MovingBallExample.class);

                                            startActivity(help);

                                        }

                                        if (iLevel == 7) {

                                            Intent help = new Intent(ScrollMenu.this, MovingBallExample.class);

                                            startActivity(help);

                                        }

                                        if (iLevel == 8) {

                                            Intent help = new Intent(ScrollMenu.this, MovingBallExample.class);

                                            startActivity(help);

                                        }

                                        iItemClicked = -1;

                                }

                        });

                }

        }

        @Override

        public boolean onKeyDown(final int pKeyCode, final KeyEvent pEvent) { 

            // Maybe the user decides to use Android buttons instead? Lets try to stop the user from quitting with the back button, by accident.

            if (pKeyCode == KeyEvent.KEYCODE_BACK

                    && pEvent.getAction() == KeyEvent.ACTION_DOWN) { // Check if the back button is being pressed

                showExitDialog(); // Run the showExitDialog.

                return true;

            }

            return super.onKeyDown(pKeyCode, pEvent);

        }

        public void showExitDialog() { // Here a showExitDialog is prepared. Its a kind of submenu, but since it is very simple its all done without XML

            AlertDialog.Builder builder = new AlertDialog.Builder(ScrollMenu.this); // Making an AlerDialog, its an Android feature

            builder.setMessage("Are you sure you want to exit?")

                    .setCancelable(false)

                    .setTitle("EXIT")

                    .setPositiveButton("Yes",

                            new DialogInterface.OnClickListener() {

                                public void onClick(DialogInterface dialog, int id) {

                                    ScrollMenu.this.finish(); // if yes is clicked, close this class. If this class had been opened by another class, we would return to that class.

                                }

                            })

                    .setNegativeButton("No", new DialogInterface.OnClickListener() {

                        public void onClick(DialogInterface dialog, int id) {

                            dialog.cancel(); // Of the NO choice is clicked, we cancel the AlertDialog and go back to Menuactivity2

                        }

                    });

            AlertDialog alert = builder.create(); // This takes the AlertDialog and prepares it

            alert.setIcon(R.drawable.icon); // Puts the application icon in the drawable folder into the dialog

            alert.show(); // shows the alert dialog

        }

}

 

//Version 0

import java.util.ArrayList;

import java.util.List;

import org.anddev.andengine.engine.Engine;

import org.anddev.andengine.engine.camera.Camera;

import org.anddev.andengine.engine.options.EngineOptions;

import org.anddev.andengine.engine.options.EngineOptions.ScreenOrientation;

import org.anddev.andengine.engine.options.resolutionpolicy.FillResolutionPolicy;

import org.anddev.andengine.entity.primitive.Rectangle;

import org.anddev.andengine.entity.scene.Scene;

import org.anddev.andengine.entity.scene.Scene.IOnSceneTouchListener;

import org.anddev.andengine.entity.scene.background.ColorBackground;

import org.anddev.andengine.entity.sprite.Sprite;

import org.anddev.andengine.entity.util.FPSLogger;

import org.anddev.andengine.input.touch.TouchEvent;

import org.anddev.andengine.input.touch.detector.ClickDetector;

import org.anddev.andengine.input.touch.detector.ClickDetector.IClickDetectorListener;

import org.anddev.andengine.input.touch.detector.ScrollDetector;

import org.anddev.andengine.input.touch.detector.ScrollDetector.IScrollDetectorListener;

import org.anddev.andengine.input.touch.detector.SurfaceScrollDetector;

import org.anddev.andengine.opengl.font.Font;

import org.anddev.andengine.opengl.font.FontFactory;

import org.anddev.andengine.opengl.texture.TextureOptions;

import org.anddev.andengine.opengl.texture.atlas.bitmap.BitmapTextureAtlas;

import org.anddev.andengine.opengl.texture.atlas.bitmap.BitmapTextureAtlasTextureRegionFactory;

import org.anddev.andengine.opengl.texture.region.TextureRegion;

import org.anddev.andengine.ui.activity.BaseGameActivity;

import android.content.Intent;

import android.graphics.Color;

import android.widget.Toast;

/**

 * 

 * @author Knoll Florian

 * @email myfknoll@gmail.com

 *

 */

public class MenuScrollerActivity extends BaseGameActivity implements IScrollDetectorListener, IOnSceneTouchListener, IClickDetectorListener {

        // ===========================================================

        // Constants

        // ===========================================================

        protected static int CAMERA_WIDTH = 480;

        protected static int CAMERA_HEIGHT = 320;

        protected static int FONT_SIZE = 24;

        protected static int PADDING = 50;

        protected static int MENUITEMS = 7;

        // ===========================================================

        // Fields

        // ===========================================================

        private Scene mScene;

        private Camera mCamera;

        private Font mFont; 

        private BitmapTextureAtlas mFontTexture;     

        private BitmapTextureAtlas mMenuTextureAtlas;        

        private TextureRegion mMenuLeftTextureRegion;

        private TextureRegion mMenuRightTextureRegion;

        private Sprite menuleft;

        private Sprite menuright;

        // Scrolling

        private SurfaceScrollDetector mScrollDetector;

        private ClickDetector mClickDetector;

        private float mMinX = 0;

        private float mMaxX = 0;

        private float mCurrentX = 0;

        private int iItemClicked = -1;

        private Rectangle scrollBar;        

        private List<TextureRegion> columns = new ArrayList<TextureRegion>();

        // ===========================================================

        // Constructors

        // ===========================================================

        // ===========================================================

        // Getter & Setter

        // ===========================================================

        // ===========================================================

        // Methods for/from SuperClass/Interfaces

        // ===========================================================

        @Override

        public void onLoadResources() {

                // Paths

                FontFactory.setAssetBasePath("font/");

                BitmapTextureAtlasTextureRegionFactory.setAssetBasePath("gfx/");

                // Font

                this.mFontTexture = new BitmapTextureAtlas(256, 256);

                this.mFont = FontFactory.createFromAsset(this.mFontTexture, this, "Plok.TTF", FONT_SIZE, true, Color.BLACK);

                this.mEngine.getTextureManager().loadTextures(this.mFontTexture);

                this.mEngine.getFontManager().loadFonts(this.mFont);

                //Images for the menu

                for (int i = 0; i < MENUITEMS; i++) {                

                    BitmapTextureAtlas mMenuBitmapTextureAtlas = new BitmapTextureAtlas(256,256, TextureOptions.BILINEAR_PREMULTIPLYALPHA);

                    TextureRegion mMenuTextureRegion = BitmapTextureAtlasTextureRegionFactory.createFromAsset(mMenuBitmapTextureAtlas, this, "menu"+i+".png", 0, 0);

                    this.mEngine.getTextureManager().loadTexture(mMenuBitmapTextureAtlas);

                    columns.add(mMenuTextureRegion);

                }

                //Textures for menu arrows

                this.mMenuTextureAtlas = new BitmapTextureAtlas(128,128, TextureOptions.BILINEAR_PREMULTIPLYALPHA);

                this.mMenuLeftTextureRegion = BitmapTextureAtlasTextureRegionFactory.createFromAsset(mMenuTextureAtlas, this, "menu_left.png", 0, 0);

                this.mMenuRightTextureRegion = BitmapTextureAtlasTextureRegionFactory.createFromAsset(mMenuTextureAtlas, this, "menu_right.png",64, 0);

                this.mEngine.getTextureManager().loadTexture(mMenuTextureAtlas);

        }

        @Override

        public Engine onLoadEngine() {

                this.mCamera = new Camera(0, 0, CAMERA_WIDTH, CAMERA_HEIGHT);

                final EngineOptions engineOptions = new EngineOptions(true, ScreenOrientation.LANDSCAPE, new FillResolutionPolicy(), this.mCamera);

                engineOptions.getTouchOptions().setRunOnUpdateThread(true);

                final Engine engine = new Engine(engineOptions);

                return engine;

        }

        @Override

        public Scene onLoadScene() {

                this.mEngine.registerUpdateHandler(new FPSLogger());

                this.mScene = new Scene();

                this.mScene.setBackground(new ColorBackground(0, 0, 0));

                this.mScrollDetector = new SurfaceScrollDetector(this);

                this.mClickDetector = new ClickDetector(this);

                this.mScene.setOnSceneTouchListener(this);

                this.mScene.setTouchAreaBindingEnabled(true);

                this.mScene.setOnSceneTouchListenerBindingEnabled(true);

                CreateMenuBoxes();

                return this.mScene;

        }

        @Override

        public boolean onSceneTouchEvent(final Scene pScene, final TouchEvent pSceneTouchEvent) {

                this.mClickDetector.onTouchEvent(pSceneTouchEvent);

                this.mScrollDetector.onTouchEvent(pSceneTouchEvent);

                return true;

        }

        @Override

        public void onScroll(final ScrollDetector pScollDetector, final TouchEvent pTouchEvent, final float pDistanceX, final float pDistanceY) {

                //Disable the menu arrows left and right (15px padding)

                if(mCamera.getMinX()<=15)

                     menuleft.setVisible(false);

                 else

                     menuleft.setVisible(true);

                 if(mCamera.getMinX()>mMaxX-15)

                     menuright.setVisible(false);

                 else

                     menuright.setVisible(true);

                //Return if ends are reached

                if ( ((mCurrentX - pDistanceX) < mMinX)  ){                    

                    return;

                }else if((mCurrentX - pDistanceX) > mMaxX){

                    return;

                }

                //Center camera to the current point

                this.mCamera.offsetCenter(-pDistanceX,0 );

                mCurrentX -= pDistanceX;

                //Set the scrollbar with the camera

                float tempX =mCamera.getCenterX()-CAMERA_WIDTH/2;

                // add the % part to the position

                tempX+= (tempX/(mMaxX+CAMERA_WIDTH))*CAMERA_WIDTH;      

                //set the position

                scrollBar.setPosition(tempX, scrollBar.getY());

                //set the arrows for left and right

                menuright.setPosition(mCamera.getCenterX()+CAMERA_WIDTH/2-menuright.getWidth(),menuright.getY());

                menuleft.setPosition(mCamera.getCenterX()-CAMERA_WIDTH/2,menuleft.getY());

                //Because Camera can have negativ X values, so set to 0

                if(this.mCamera.getMinX()<0){

                    this.mCamera.offsetCenter(0,0 );

                    mCurrentX=0;

                }

        }

        @Override

        public void onClick(ClickDetector pClickDetector, TouchEvent pTouchEvent) {

                loadLevel(iItemClicked);

        };

        // ===========================================================

        // Methods

        // ===========================================================

        private void CreateMenuBoxes() {

             int spriteX = PADDING;

             int spriteY = PADDING;

             //current item counter

             int iItem = 1;

             for (int x = 0; x < columns.size(); x++) {

                 //On Touch, save the clicked item in case it's a click and not a scroll.

                 final int itemToLoad = iItem;

                 Sprite sprite = new Sprite(spriteX,spriteY,columns.get(x)){

                     public boolean onAreaTouched(final TouchEvent pSceneTouchEvent, final float pTouchAreaLocalX, final float pTouchAreaLocalY) {

                         iItemClicked = itemToLoad;

                         return false;

                     }                     

                 };                 

                 iItem++;

                 this.mScene.attachChild(sprite);                 

                 this.mScene.registerTouchArea(sprite);                 

                 spriteX += 20 + PADDING+sprite.getWidth();

            }

             mMaxX = spriteX - CAMERA_WIDTH;

             //set the size of the scrollbar

             float scrollbarsize = CAMERA_WIDTH/((mMaxX+CAMERA_WIDTH)/CAMERA_WIDTH);

             scrollBar = new Rectangle(0,CAMERA_HEIGHT-20,scrollbarsize, 20);

             scrollBar.setColor(1,0,0);

             this.mScene.attachChild(scrollBar);

             menuleft = new Sprite(0,CAMERA_HEIGHT/2-mMenuLeftTextureRegion.getHeight()/2,mMenuLeftTextureRegion);

             menuright = new Sprite(CAMERA_WIDTH-mMenuRightTextureRegion.getWidth(),CAMERA_HEIGHT/2-mMenuRightTextureRegion.getHeight()/2,mMenuRightTextureRegion);

             this.mScene.attachChild(menuright);

             menuleft.setVisible(false);

             this.mScene.attachChild(menuleft);

        }

        @Override

        public void onLoadComplete() {

        }

        //Here is where you call the item load.

        private void loadLevel(final int iLevel) {

                if (iLevel != -1) {

                        runOnUiThread(new Runnable() {

                                @Override

                                public void run() {

                                        Toast.makeText(MenuScrollerActivity.this, "Load Item" + String.valueOf(iLevel), Toast.LENGTH_SHORT).show();

                                        iItemClicked = -1;

                                }

                        });

                }

        }

}