NotificationCenter的基本使用：</span>

init方法中：</span>

NotificationCenter::getInstance()->addObserver(this,callfuncO_selector(HelloWorld::call2),"abc",nullptr); //添加观察对象  
	
	auto b1 = MenuItemImage::create("CloseNormal.png","CloseNormal.png",CC_CALLBACK_0(HelloWorld::call,this)); //按钮   
	auto menu = Menu::create(b1,nullptr);
	this->addChild(menu);

对应的方法：</span>

void HelloWorld::call()
{
log("call()");
NotificationCenter::getInstance()->postNotification("abc",this);
}


void HelloWorld::call2(Ref* obj)
{
log("call2()");
auto s = Sprite::create("CloseNormal.png");
s->setPosition(Vec2(100,100));
this->addChild(s);
}

</pre><pre name="code" class="cpp">最后：

HelloWorld::~HelloWorld()
{
<span style="white-space:pre">	</span>NotificationCenter::getInstance()->removeObserver(this,"abc");  //取消监听   
<span style="white-space:pre">	</span>//NotificationCenter::getInstance()->removeAllObservers(this);
}