解释cocos2dx的HelloWorldScene的类

在之前的AppDelegate中的

    //这里可以换场景de

    // create a scene. it's an autorelease object

    CCScene *pScene = HelloWorld::scene();

    

    // run

    pDirector->runWithScene(pScene);

 默认导演将Hello World 这个场景展示在模拟器中

注释HelloWorldScene.h

#ifndef __HELLOWORLD_SCENE_H__

#define __HELLOWORLD_SCENE_H__



#include "cocos2d.h"



class HelloWorld : public cocos2d::CCLayer

{

public:

    // Method 'init' in cocos2d-x returns bool, instead of 'id' in cocos2d-iphone (an object pointer)

    //初始化函数

    virtual bool init();



    // there's no 'id' in cpp, so we recommend to return the class instance pointer

    //静态创建函数

    static cocos2d::CCScene* scene();

    

    // a selector callback

    //menu 菜单的一个回调函数  用于响应CCMenuItemImage

    void menuCloseCallback(CCObject* pSender);



    // preprocessor macro for "static create()" constructor ( node() deprecated )

    //备注1

    CREATE_FUNC(HelloWorld);

};



#endif // __HELLOWORLD_SCENE_H__

 HelloWorldScene.cpp注释

#include "HelloWorldScene.h"

#include "SimpleAudioEngine.h"



using namespace cocos2d;

using namespace CocosDenshion;



CCScene* HelloWorld::scene()

{

    //创建一个场景

    // 'scene' is an autorelease object

    CCScene *scene = CCScene::create();

    //创建一个HelloWorld的层

    // 'layer' is an autorelease object

    HelloWorld *layer = HelloWorld::create();

 //将层放到场景中去

    // 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()

{//  调用父类初始化函数

    //////////////////////////////

    // 1. super init first

    if ( !CCLayer::init() )

    {

        return false;

    }



    /////////////////////////////

    // 2. add a menu item with "X" image, which is clicked to quit the program

    //    you may modify it.



    // add a "close" icon to exit the progress. it's an autorelease object

     //将一个相片创建菜单项 并调用方法menuCloseCallback

    CCMenuItemImage *pCloseItem = CCMenuItemImage::create(

                                        "CloseNormal.png",

                                        "CloseSelected.png",

                                        this,

                                        menu_selector(HelloWorld::menuCloseCallback) );

    //开关相片的位置

    pCloseItem->setPosition( ccp(CCDirector::sharedDirector()->getWinSize().width - 20, 20) );



    //将一个已经创建好的菜单项加入菜单中 并声称一个菜单对象的实例

    // create menu, it's an autorelease object

    CCMenu* pMenu = CCMenu::create(pCloseItem, NULL);

     // 设置菜单的位置

    pMenu->setPosition( CCPointZero );

    // 将菜单加入当前的layer里  并设置z轴为1

    this->addChild(pMenu, 1);



    /////////////////////////////

    // 3. add your codes below...



    // add a label shows "Hello World"

    // create and initialize a label

    //创建一个文本对象 并设置字体和大小

    CCLabelTTF* pLabel = CCLabelTTF::create("Hello World", "Thonburi", 34);



//    获取当前设备的尺寸

    // ask director the window size

    CCSize size = CCDirector::sharedDirector()->getWinSize();

//设置文本的位置

    // position the label on the center of the screen

    pLabel->setPosition( ccp(size.width / 2, size.height - 20) );



    // add the label as a child to this layer

//    将文本放大layer层中  和menu的设置轴是一样的  就是同一层

    this->addChild(pLabel, 1);



    // add "HelloWorld" splash screen"

//    设置一个精灵  并且放入图片

    CCSprite* pSprite = CCSprite::create("HelloWorld.png");

//精灵的位置

    // position the sprite on the center of the screen

    pSprite->setPosition( ccp(size.width/2, size.height/2) );

//把精灵放到layer中去   但是在底层

    // add the sprite as a child to this layer

    this->addChild(pSprite, 0);

    

    return true;

}



void HelloWorld::menuCloseCallback(CCObject* pSender)

{

//    程序退出

    CCDirector::sharedDirector()->end();

//判定是否为ios设备

#if (CC_TARGET_PLATFORM == CC_PLATFORM_IOS)

    exit(0);

#endif

}

相信能看明白