云朵，英雄走起来

1.在场景中添加云朵，并让云朵自动向左或者向右移动

2.添加一个英雄，并且设置上、下、左、右几个按钮，点击按钮，英雄就向相应方向移动

下面来实现一下这个功能：

Size visibleSize = Director::getInstance()->getVisibleSize();
Vec2 origin = Director::getInstance()->getVisibleOrigin();

auto up = MenuItemFont::create("上",CC_CALLBACK_1(HelloWorld::menuCallback,this));
up->setPosition(400,100);
up->setTag(102);
auto down = MenuItemFont::create("下",CC_CALLBACK_1(HelloWorld::menuCallback,this));
down->setPosition(400,50);
down->setTag(103);
auto left = MenuItemFont::create("左",CC_CALLBACK_1(HelloWorld::menuCallback,this));
left->setPosition(350,75);
left->setTag(104);
auto right = MenuItemFont::create("右",CC_CALLBACK_1(HelloWorld::menuCallback,this));
right->setPosition(450,75);
right->setTag(105);

auto menu = Menu::create(closeItem,up,down,left,right,NULL);
menu->setPosition(Vec2::ZERO);
this->addChild(menu,
1);

auto bg = Sprite::create("bg.jpg");
bg->setPosition(Vec2(origin.x+visibleSize.width/2,origin.y+visibleSize.height/2));
this->addChild(bg);

auto cloud1 = Sprite::create("cloud1.jpg"); //云朵1
cloud1->setPosition(Vec2(100,200));
this->addChild(cloud1);
cloud1->setScale(0.3);
cloud1->setTag(100);

auto cloud2 = Sprite::create("cloud2.jpg"); //云朵2
cloud2->setPosition(Vec2(200,250));
this->addChild(cloud2);
cloud2->setScale(0.3);
cloud2->setTag(101);

auto hero = Sprite::create("hero.png"); //添加英雄
hero->setPosition(Vec2(100,100));
hero->setScale(0.1);
this->addChild(hero);
hero->setTag(106);

//通过计划任务来让云朵动起来
this->schedule(schedule_selector(HelloWorld::moveCloud),0.1);

returntrue;
}

//云朵移动的函数实现 获取Tag->获取对象->操作对象
void HelloWorld::moveCloud(float t){
this->getChildByTag(100)->setPositionX(this->getChildByTag(100)->getPositionX()+10);
if (this->getChildByTag(100)->getPositionX()>480)
{
this->getChildByTag(100)->setPositionX(0);
}

this->getChildByTag(101)->setPositionX(this->getChildByTag(101)->getPositionX()+15);
if (this->getChildByTag(101)->getPositionX()>480)
{
this->getChildByTag(101)->setPositionX(0);
}
}

//实现按钮的功能
void HelloWorld::menuCallback(Ref* pSender)
{
auto item = (MenuItemFont* )pSender;
switch (item->getTag()) {
case
102:
this->getChildByTag(106)->setPositionY(this->getChildByTag(106)->getPositionY()+10);
if (this->getChildByTag(106)->getPositionY()>320)
{
this->getChildByTag(106)->setPositionY(0);
}
break;
case
103:
this->getChildByTag(106)->setPositionY(this->getChildByTag(106)->getPositionY()-10);
if (this->getChildByTag(106)->getPositionY()<0)
{
this->getChildByTag(106)->setPositionY(320);
}
break;
case
104:
this->getChildByTag(106)->setPositionX(this->getChildByTag(106)->getPositionX()-10);
if (this->getChildByTag(106)->getPositionX()<0)
{
this->getChildByTag(106)->setPositionX(480);
}
break;
case
105:
this->getChildByTag(106)->setPositionX(this->getChildByTag(106)->getPositionX()+10);
if (this->getChildByTag(106)->getPositionX()>480)
{
this->getChildByTag(106)->setPositionX(0);
}
default:
break;
}