java - AndEngine如何让 Sprite 在调用jump方法时不跳转

Question

所以我有这个方法，当我触摸屏幕时，我的 Sprite 会跳跃。现在的问题是，当我连续触摸屏幕时， Sprite 会一次又一次地跳跃。我想做的是，如果它跳跃，除非我的 Sprite 落地，否则无法调用跳跃方法。

这是代码。

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;
}

我不知道为什么 beginContact 和 endContact 没有初始化。我应该做些什么来初始化它吗？例如更新处理程序？联系人监听器？

Answer 1

你需要有一个方法来告诉你你的玩家是否在跳跃。

public void jump(AnimatedSprite sprite){

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

在此方法中，您应该输入计算玩家是否跳跃的方法。就像他正在触摸墙壁一样(如果玩家的 body (x,y) 在墙壁(矩形)中)

好吧，你正在使用 box2d 来制裁剪理 =)

你必须创建一个ContactListener，你必须实现这个类和你想要添加的函数。 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);

接触对象将计算正在接触的对象(夹具)。你只需要在 body 接触时检查并将jump设置为false，在调用jump时将jump设置为true，然后你就可以跳跃，将jump设置为true；

可以吗？

@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;
}

这是错误的..我只会这样认为:

@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
}

以及一种跳转方法(不是两种):

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

你看到了吗？;