FadeIn

bool HelloWorld::init()
{
    if(!Layer::init())
    {
        return false;
    }

    auto spr = Sprite::create("Icon-57.png");
    spr->setPosition(Point(100, 100));
    spr->setOpacity(0);
    this->addChild(spr);

    auto action = FadeIn::create(3.0);
    spr->runAction(action);

    return true;
}