AndEngine how to make a sprite not jump if jump method is called

Question

So I have this method that when i touch the screen my sprite will jump. Now the problem is when I continuously touch the screen the sprite will jump again and again. What I want to do is if it jumps, the jump method cannot be called unless my sprite hits the ground.

Here is the code.

public class PhyiscsActivity extends BaseGameActivity implements IAccelerometerListener, IOnSceneTouchListener{


private static final int CAMERA_WIDTH = 720;
private static final int CAMERA_HEIGHT = 480;
private Camera mCamera;
private BitmapTextureAtlas mBitmapTextureAtlas;
private TiledTextureRegion mTextureRegion;
private Scene mScene;
private FixtureDef mFixtureDef = PhysicsFactory.createFixtureDef(1,-10f, 0.5f);
private PhysicsWorld mPhysicsWorld;
private Body body;
private AnimatedSprite facebox;
private FixtureDef wallfixture = PhysicsFactory.createFixtureDef(-1,0.5f, 0.5f);
@Override
public Engine onLoadEngine() {
    // TODO Auto-generated method stub
    this.mCamera = new Camera(0,0,CAMERA_WIDTH, CAMERA_HEIGHT);
    final EngineOptions mEngineOptions = new EngineOptions(true, ScreenOrientation.LANDSCAPE, new RatioResolutionPolicy(CAMERA_WIDTH, CAMERA_HEIGHT),this.mCamera);
    mEngineOptions.getTouchOptions().setRunOnUpdateThread(true);
    return new Engine(mEngineOptions);
}

@Override
public void onLoadResources() {
    // TODO Auto-generated method stub
    this.mBitmapTextureAtlas = new BitmapTextureAtlas(128,128, TextureOptions.BILINEAR_PREMULTIPLYALPHA);
    this.mTextureRegion = BitmapTextureAtlasTextureRegionFactory.createTiledFromAsset(mBitmapTextureAtlas, this, "gfx/face_box_tiled.png", 0, 0, 2, 1);
    this.mEngine.getTextureManager().loadTexture(this.mBitmapTextureAtlas);
}

@Override
public Scene onLoadScene() {
    // TODO Auto-generated method stub
    this.mEngine.registerUpdateHandler(new FPSLogger());
    this.mScene = new Scene();
    this.mScene.setBackground(new ColorBackground(1,1,1));
    this.mPhysicsWorld = new PhysicsWorld(new Vector2(0,SensorManager.GRAVITY_EARTH),false);

    // This is the walls
    final Shape roof = new Rectangle(0, 0, CAMERA_WIDTH, 2);
    final Shape ground = new Rectangle(0,CAMERA_HEIGHT - 2,CAMERA_WIDTH,2);
    final Shape left = new Rectangle(0,0,2,CAMERA_HEIGHT);
    final Shape right = new Rectangle(CAMERA_WIDTH -2, 0,2,CAMERA_HEIGHT);
    PhysicsFactory.createBoxBody(this.mPhysicsWorld, ground, BodyType.StaticBody, wallfixture);
    PhysicsFactory.createBoxBody(this.mPhysicsWorld,  roof, BodyType.StaticBody, wallfixture);
    PhysicsFactory.createBoxBody(this.mPhysicsWorld, left, BodyType.StaticBody, wallfixture);
    PhysicsFactory.createBoxBody(this.mPhysicsWorld, right, BodyType.StaticBody, wallfixture);

    // This is the Sprite
    facebox = new AnimatedSprite(30,(CAMERA_HEIGHT - 2) -  this.mTextureRegion.getHeight()  ,this.mTextureRegion);
    body = PhysicsFactory.createBoxBody(this.mPhysicsWorld, facebox, BodyType.DynamicBody, mFixtureDef);
    this.mScene.attachChild(facebox);

    this.mScene.registerUpdateHandler(this.mPhysicsWorld);
    this.mPhysicsWorld.registerPhysicsConnector(new PhysicsConnector(facebox,body,true,true));
    this.mScene.setOnSceneTouchListener(this);
    return this.mScene;

}

@Override
public void onLoadComplete() {
    // TODO Auto-generated method stub

}


//Accelerometer
@Override
public void onAccelerometerChanged(AccelerometerData pAccelerometerData) {
    // TODO Auto-generated method stub
    final Vector2 gravity = Vector2Pool.obtain(pAccelerometerData.getX()* 3, 10);
    this.mPhysicsWorld.setGravity(gravity);
    Vector2Pool.recycle(gravity);
}

@Override
protected void onResume() {
    // TODO Auto-generated method stub
    super.onResume();
    this.enableAccelerometerSensor(this);
}

@Override
protected void onPause() {
    // TODO Auto-generated method stub
    super.onPause();
    this.disableAccelerometerSensor();
}

//This is where i make the sprite jump
@Override
public boolean onSceneTouchEvent(Scene pScene, TouchEvent pSceneTouchEvent) {
    pSceneTouchEvent.isActionDown();{
        this.jump(facebox);
    }
    return false;


}
public void jump(AnimatedSprite sprite){
    boolean jumping = false;
    if(!jumping ){
        body.setLinearVelocity(new Vector2(body.getLinearVelocity().x,-8f));        
        }
    }

public void jump(AnimatedSprite sprite){
    if(!jumping){
       body.setLinearVelocity(new Vector2(body.getLinearVelocity().x,-10));     
       jumping = true;
    }

    }

@Override
public void beginContact(Contact contact) {
    // TODO Auto-generated method stub
    jumping = true;
}

@Override
public void endContact(Contact contact) {
    // TODO Auto-generated method stub
jumping = false;
}

I don't know why the beginContact and endContact isn't initialzing. are there things that i should do to initialize this? example like updating a handler? contactlistener?

Answer 1

You need to have a method wich tell you if your player is jumping or not.

public void jump(AnimatedSprite sprite){

    if( isJumping(sprite)){
        body.setLinearVelocity(new Vector2(body.getLinearVelocity().x,-8f));        
        }

In this method you should put the way to compute if the player is jumping. Like if he is touching a wall (if player's body (x,y) is in a wall (rectangle))

Ok you are using box2d to make physics =)

You have to create a ContactListener, you have to implement this class and the function ou want to add. http://code.google.com/p/andenginephysicsbox2dextension/source/browse/src/com/badlogic/gdx/physics/box2d/ContactListener.java?r=1605f6e82f710ef9ebbe07632d6b055239d3b520

public void beginContact (Contact contact);
public void endContact (Contact contact);

The contact object will countain your objects (Fixture) that are touching. You just have to check and set jumping to false when the body is touching and true when you call jump and you can jump, set jumping to true;

Ok?

@Override
public void beginContact(Contact contact) {
    // TODO Auto-generated method stub
    jumping = true;
}

@Override
public void endContact(Contact contact) {
    // TODO Auto-generated method stub
jumping = false;
}

This is false.. I would think of it like that only:

@Override
public void beginContact(Contact contact) {
    jumping = false; //you touched ground so you aren't jumping anymore
}

@Override
public void endContact(Contact contact) {
jumping = true; //you leave ground so you're jumping
}

and one jump method (not two):

   public void jump(AnimatedSprite sprite){
        if(!jumping ){
            jumping = true;
            body.setLinearVelocity(new Vector2(body.getLinearVelocity().x,-8f));        
            }
        }

You see?;