// on "init" you need to initialize your instancebool HelloWorld::init(){    //////////////////////////////    // 1. super init first    if ( !Layer::init() )    {        return false;    }        Size visibleSize = Director::getInstance()->getVisibleSize();    Vec2 origin = Director::getInstance()->getVisibleOrigin();           auto cache = SpriteFrameCache::getInstance();    cache->addSpriteFramesWithFile("anim.plist");        Vector<SpriteFrame*> vec;    char name[15];    memset(name, 0, 15);        for (int i=0; i<20; i++) {        sprintf(name, "anim%04d",i);        vec.pushBack(cache->getSpriteFrameByName(name));    }        Animation *animation = Animation::createWithSpriteFrames(vec,0.1f);    Animate *animate = Animate::create(animation);        auto sprite = Sprite::create();    addChild(sprite);    sprite->setPosition(200, 200);    sprite->runAction(RepeatForever::create(animate));    return true;}