Move background on button click andengine - andengine

Question

I am new in android game development,I have two buttons on screen , one for forward and one for reverse, also one player sprite.I want to move large background on buttons click.
I have idea about auto-parallax background,but how can i move background on buttons click?
please help
I am doing some thing like this, but it is not smooth and also i think this is not a good approach
public class MainActivity extends SimpleBaseGameActivity implements IOnSceneTouchListener {
private static final int CAMERA_WIDTH = 480;
private static final int CAMERA_HEIGHT = 320;
// ===========================================================
// Fields
// ===========================================================
BitmapTextureAtlas ForwardAtlas,backgroundAtlas,backAtlas,mFontTexture;
ITextureRegion ForwardAtlasRegion,backgroundAtlasRegion,backAtlasRegion;
Sprite ForwardSprite,backgroundSprite,backSprite;
AnimatedSprite player;
private BitmapTextureAtlas mBitmapTextureAtlas;
private TiledTextureRegion mPlayerTextureRegion;
SequenceEntityModifier modifier;
AutoParallaxBackground autoParallaxBackground;
boolean flag=true;
Scene scene;
private Font mFont;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}
#Override
public EngineOptions onCreateEngineOptions() {
// TODO Auto-generated method stub
final Camera camera = new Camera(0, 0, CAMERA_WIDTH, CAMERA_HEIGHT);
EngineOptions eo = new EngineOptions(true, ScreenOrientation.LANDSCAPE_FIXED,new FillResolutionPolicy(),camera);
return eo;
}
#Override
protected void onCreateResources() {
// TODO Auto-generated method stub
BitmapTextureAtlasTextureRegionFactory.setAssetBasePath("gfx/");
this.mBitmapTextureAtlas = new BitmapTextureAtlas(256, 128, TextureOptions.BILINEAR);
this.mPlayerTextureRegion = BitmapTextureAtlasTextureRegionFactory.createTiledFromAsset(this.mBitmapTextureAtlas, this, "player.png", 0, 0, 3, 4);
this.mBitmapTextureAtlas.load(this.getTextureManager());
ForwardAtlas = new BitmapTextureAtlas(60,60);
ForwardAtlas.load(getTextureManager());
ForwardAtlasRegion = BitmapTextureAtlasTextureRegionFactory.createFromAsset(ForwardAtlas, getApplicationContext(), "forward.png",0,0);
backAtlas = new BitmapTextureAtlas(60,60);
backAtlas.load(getTextureManager());
backAtlasRegion = BitmapTextureAtlasTextureRegionFactory.createFromAsset(backAtlas, getApplicationContext(), "Back.png",0,0);
backgroundAtlas = new BitmapTextureAtlas(1000,480);
backgroundAtlas.load(getTextureManager());
backgroundAtlasRegion = BitmapTextureAtlasTextureRegionFactory.createFromAsset(backgroundAtlas, getApplicationContext(), "background-2.png",0,0);
this.mFontTexture = new BitmapTextureAtlas(256, 256, TextureOptions.BILINEAR_PREMULTIPLYALPHA);
this.mFont = new Font(this.mFontTexture, Typeface.create(Typeface.DEFAULT, Typeface.BOLD), 32, true, Color.BLACK);
this.mEngine.getTextureManager().loadTexture(this.mFontTexture);
this.getFontManager().loadFont(this.mFont);
}
#Override
protected Scene onCreateScene() {
// TODO Auto-generated method stub
this.mEngine.registerUpdateHandler(new FPSLogger());
scene = new Scene();
final int playerX = (CAMERA_WIDTH - this.mPlayerTextureRegion.getWidth()) / 2;
final int playerY = CAMERA_HEIGHT - this.mPlayerTextureRegion.getHeight() - 5;
//final Text x = new Text(100, 60, this.mFont,Integer.toString(playerX) , HorizontalAlign.CENTER);
//final Text y = new Text(120, 90, this.mFont,Integer.toString(playerY) , HorizontalAlign.CENTER);
player = new AnimatedSprite(playerX, playerY, this.mPlayerTextureRegion);
player.setScaleCenterY(this.mPlayerTextureRegion.getHeight());
player.setScale(2);
player.animate(new long[]{200, 200, 200}, 6, 8, true);
ForwardSprite = new Sprite(390,250, ForwardAtlasRegion);
backSprite = new Sprite(40,250, backAtlasRegion);
backgroundSprite = new Sprite(0,0,backgroundAtlasRegion);
autoParallaxBackground = new AutoParallaxBackground(0, 0, 0, 5);
autoParallaxBackground.attachParallaxEntity(new ParallaxEntity(-10.0f, new Sprite(0, CAMERA_HEIGHT - this.backgroundAtlasRegion.getHeight(), this.backgroundAtlasRegion)));
scene.setBackground(autoParallaxBackground);
scene.attachChild(player);
scene.attachChild(ForwardSprite);
scene.registerTouchArea(ForwardSprite);
scene.attachChild(backSprite);
scene.registerTouchArea(backSprite);
scene.setOnAreaTouchListener(new IOnAreaTouchListener() {
#Override
public boolean onAreaTouched(TouchEvent pSceneTouchEvent,
ITouchArea pTouchArea, float pTouchAreaLocalX,
float pTouchAreaLocalY)
{
if(pSceneTouchEvent.isActionUp())
{
autoParallaxBackground.attachParallaxEntity(new ParallaxEntity(0.0f, new Sprite(0, CAMERA_HEIGHT - backgroundAtlasRegion.getHeight(), backgroundAtlasRegion)));
if(pTouchArea == ForwardSprite)
if(pTouchArea == backSprite)
return true;
}
if(pSceneTouchEvent.isActionMove()) {
if(pTouchArea == ForwardSprite)
{
player.animate(new long[]{200, 200, 200}, 3, 5, true);
autoParallaxBackground.attachParallaxEntity(new ParallaxEntity(-10.0f, new Sprite(0, CAMERA_HEIGHT - backgroundAtlasRegion.getHeight(), backgroundAtlasRegion)));
//backgroundSprite.setPosition(backgroundSprite.getX()-5, backgroundSprite.getY());
}
if(pTouchArea == backSprite)
{
player.animate(new long[]{200, 200, 200}, 9, 11, true);
autoParallaxBackground.attachParallaxEntity(new ParallaxEntity(10.0f, new Sprite(0, CAMERA_HEIGHT - backgroundAtlasRegion.getHeight(), backgroundAtlasRegion)));
//backgroundSprite.setPosition(backgroundSprite.getX()+5, backgroundSprite.getY());
}
return true;
}
return false;
}
});
//scene.setOnSceneTouchListener(this);
return scene;
}

Answer 1

I've just answered similiar question. Please take a look at stop and start auto parallaxbackground in andengine
There isn't such function provided in andengine so you will need extend or add some features in AutoParallaxBacground class of AndEngine library.
package org.andengine.entity.scene.background;
/**
* (c) 2010 Nicolas Gramlich
* (c) 2011 Zynga Inc.
*
* #author Nicolas Gramlich
* #since 19:44:31 - 19.07.2010
*/
public class AutoParallaxBackground extends ParallaxBackground {
// ===========================================================
// Constants
// ===========================================================
// ===========================================================
// Fields
// ===========================================================
private float mParallaxChangePerSecond;
private boolean movingForward;
private boolean movingBackward;
// ===========================================================
// Constructors
// ===========================================================
public AutoParallaxBackground(final float pRed, final float pGreen, final float pBlue, final float pParallaxChangePerSecond) {
super(pRed, pGreen, pBlue);
this.mParallaxChangePerSecond = pParallaxChangePerSecond;
}
// ===========================================================
// Getter & Setter
// ===========================================================
public void setParallaxChangePerSecond(final float pParallaxChangePerSecond) {
this.mParallaxChangePerSecond = pParallaxChangePerSecond;
}
// ===========================================================
// Methods for/from SuperClass/Interfaces
// ===========================================================
#Override
public void onUpdate(final float pSecondsElapsed) {
super.onUpdate(pSecondsElapsed);
if(movingForward)
this.mParallaxValue += this.mParallaxChangePerSecond * pSecondsElapsed;
else if (moving Backward)
this.mParallaxValue -= this.mParallaxChangePerSecond * pSecondsElapsed;
}
// ===========================================================
// Methods
// ===========================================================
public void startForward(){
this.movingBackward = false;
this.movingForward = true;
}
public void startBackward(){
this.movingForward = false;
this.movingBackward = true;
}
public void stop(){
this.movingBackward = false;
this.movingForward = false;
}
// ===========================================================
// Inner and Anonymous Classes
// ===========================================================
}
I haven't tested that solution but it should work as expected. The only thing I am not sure right now is changing incrementation to decrementation enough.