cocos2d-x之场景的生命周期

在 HelloWorldScence.cpp中的完整代码：

#include "HelloWorldScene.h"
#include "cocostudio/CocoStudio.h"
#include "ui/CocosGUI.h"

USING_NS_CC;

using namespace cocostudio::timeline;

Scene* HelloWorld::createScene()
{
    // 'scene' is an autorelease object
    auto scene = Scene::create();
    
    // 'layer' is an autorelease object
    auto layer = HelloWorld::create();

    // add layer as a child to scene
    scene->addChild(layer);

    // return the scene
    return scene;
}

// on "init" you need to initialize your instance
bool HelloWorld::init()                         //初始化层调用
{
    //////////////////////////////
    // 1. super init first
    if ( !Layer::init() )
    {
        return false;
    }
	log("HelloWorld init");
	return true;
}

void HelloWorld::onEnter(){                   //进入层时调用
	Layer::onEnter();
	log("HelloWorld onEnter");
}

void HelloWorld::onEnterTransitionDidFinish(){         //进入层而且过渡动画时动画时调用
	Layer::onEnterTransitionDidFinish();
	log("HelloWord onEnterTransitionDidFinish");
}

void HelloWorld::onExit(){                       //退出层时调用
	Layer::onExit();
	log("HelloWorld onExit");
}

void HelloWorld::onExitTransitionDidStart(){              //退出层而且过渡动画时调用
	Layer::onExitTransitionDidStart();
	log("HelloWorld onExitTransitionDidStart");
}

void HelloWorld::cleanup(){                        //层对象被清除时调用
	Layer::cleanup();
	log("HelloWorld cleanup");
}

在HelloWorldScene.h中的代码：

#ifndef __HELLOWORLD_SCENE_H__
#define __HELLOWORLD_SCENE_H__

#include "cocos2d.h"

class HelloWorld : public cocos2d::Layer
{
public:
    // there's no 'id' in cpp, so we recommend returning the class instance pointer
    static cocos2d::Scene* createScene();

    // Here's a difference. Method 'init' in cocos2d-x returns bool, instead of returning 'id' in cocos2d-iphone
    virtual bool init();

	virtual void onEnter();
	virtual void onEnterTransitionDidFinish();
	virtual void onExit();
	virtual void onExitTransitionDidStart();
	virtual void cleanup();

    // implement the "static create()" method manually
    CREATE_FUNC(HelloWorld);
};

#endif // __HELLOWORLD_SCENE_H__