Cocos2d-x 3.2 自动更新 -- 使用AssetsManager更新游戏资源包

 Android和win32已经测试通过，理论上IOS也可以。 
        1、AssetsManagerDelegateProtocol 
        AssetsManagerDelegateProtocol，用于与服务器校验版本号，更新下载资源包，并对成功、出错、下载进度等进行回调。 
        2、资源包名称 
        所下载资源包名称默认为：cocos2dx-update-temp-package.zip。  
        如果想要修改文件名，直接修改引擎下 extensions\assets-manager\AsetsManager.ccp中的TEMP_PACKAGE_FILE_NAME 
           
        3、服务器 
        下以是我的资源包路径和本版号。 
        http://shezzer.sinaapp.com/downloadTest/cocos2dx-update-temp-package.zip 
        http://shezzer.sinaapp.com/downloadTest/version.php  
        4、实现 
         
        //  Upgrade.h
        //<img src="http://img.blog.csdn.net/20140728093037654?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQvTGlhbmdzaGFvemU=/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/SouthEast" alt="" />
        //  Created by Sharezer on 14-07-26.
        //
        //
        
        #ifndef _UPGRADE_H_
        #define _UPGRADE_H_
        #include "cocos2d.h"
        #include "extensions/cocos-ext.h"
        
        class Upgrade : public cocos2d::CCLayer, public cocos2d::extension::AssetsManagerDelegateProtocol
        {
        public:
         Upgrade();
         virtual ~Upgrade();
        
         virtual bool init();
        
         void upgrade(cocos2d::Ref* pSender); //检查版本更新
         void reset(cocos2d::Ref* pSender); //重置版本
        
         virtual void onError(cocos2d::extension::AssetsManager::ErrorCode errorCode); //错误信息
         virtual void onProgress(int percent); //更新下载进度
         virtual void onSuccess(); //下载成功
         CREATE_FUNC(Upgrade);
        private:
         cocos2d::extension::AssetsManager* getAssetManager();
         void initDownloadDir(); //创建下载目录
        
        private:
         std::string _pathToSave;
         cocos2d::Label *_showDownloadInfo;
        };
        
        
        #endif
        
         
        //Upgrade.cpp
        #include "Upgrade.h"
        #include "HelloWorldScene.h"
        
        #if (CC_TARGET_PLATFORM != CC_PLATFORM_WIN32)
        #include <dirent.h>
        #include <sys/stat.h>
        #endif
        
        USING_NS_CC;
        USING_NS_CC_EXT;
        
        #define DOWNLOAD_FIEL "download" //下载后保存的文件夹名
        
        Upgrade::Upgrade():
        _pathToSave(""),
        _showDownloadInfo(NULL)
        {
        
        }
        
        Upgrade::~Upgrade()
        {
         AssetsManager* assetManager = getAssetManager();
         CC_SAFE_DELETE(assetManager);
        }
        
        bool Upgrade::init()
        {
         if (!CCLayer::init())
         {
         return false;
         }
         Size winSize = Director::getInstance()->getWinSize();
         initDownloadDir();
         _showDownloadInfo = Label::createWithSystemFont("", "Arial", 20);
         this->addChild(_showDownloadInfo);
         _showDownloadInfo->setPosition(Vec2(winSize.width / 2, winSize.height / 2 - 20));
        
        
         auto itemLabel1 = MenuItemLabel::create(
         Label::createWithSystemFont("Reset", "Arail", 20), CC_CALLBACK_1(Upgrade::reset, this));
         auto itemLabel2 = MenuItemLabel::create(
         Label::createWithSystemFont("Upgrad", "Arail", 20), CC_CALLBACK_1(Upgrade::upgrade, this));
        
         auto menu = Menu::create(itemLabel1, itemLabel2, NULL);
         this->addChild(menu);
        
         itemLabel1->setPosition(Vec2(winSize.width / 2, winSize.height / 2 + 20));
         itemLabel2->setPosition(Vec2(winSize.width / 2, winSize.height / 2 ));
        
         menu->setPosition(Vec2::ZERO);
        
         return true;
        }
        
        void Upgrade::onError(AssetsManager::ErrorCode errorCode)
        {
         if (errorCode == AssetsManager::ErrorCode::NO_NEW_VERSION)
         {
         _showDownloadInfo->setString("no new version");
         }
         else if (errorCode == AssetsManager::ErrorCode::NETWORK)
         {
         _showDownloadInfo->setString("network error");
         }
         else if (errorCode == AssetsManager::ErrorCode::CREATE_FILE)
         {
         _showDownloadInfo->setString("create file error");
         }
        }
        
        void Upgrade::onProgress(int percent)
        {
         if (percent < 0)
         return;
         char progress[20];
         snprintf(progress, 20, "download %d%%", percent);
         _showDownloadInfo->setString(progress);
        }
        
        void Upgrade::onSuccess()
        {
         CCLOG("download success");
         _showDownloadInfo->setString("download success");
         std::string path = FileUtils::getInstance()->getWritablePath() + DOWNLOAD_FIEL;
         //FileUtils::getInstance()->addSearchPath(path, true);
         auto scene = HelloWorld::scene();
         Director::getInstance()->replaceScene(scene);
        }
        
        AssetsManager* Upgrade::getAssetManager()
        {
         static AssetsManager *assetManager = NULL;
         if (!assetManager)
         {
         assetManager = new AssetsManager("http://shezzer.sinaapp.com/downloadTest/cocos2dx-update-temp-package.zip",
         "http://shezzer.sinaapp.com/downloadTest/version.php",
         _pathToSave.c_str());
         assetManager->setDelegate(this);
         assetManager->setConnectionTimeout(3);
         }
         return assetManager;
        }
        
        void Upgrade::initDownloadDir()
        {
         CCLOG("initDownloadDir");
         _pathToSave = CCFileUtils::getInstance()->getWritablePath();
         _pathToSave += DOWNLOAD_FIEL;
        CCLOG("Path: %s", _pathToSave.c_str());
        #if (CC_TARGET_PLATFORM != CC_PLATFORM_WIN32)
         DIR *pDir = NULL;
         pDir = opendir(_pathToSave.c_str());
         if (!pDir)
         {
         mkdir(_pathToSave.c_str(), S_IRWXU | S_IRWXG | S_IRWXO);
         }
        #else
         if ((GetFileAttributesA(_pathToSave.c_str())) == INVALID_FILE_ATTRIBUTES)
         {
         CreateDirectoryA(_pathToSave.c_str(), 0);
         }
        #endif
         CCLOG("initDownloadDir end");
        }
        
        void Upgrade::reset(Ref* pSender)
        {
         _showDownloadInfo->setString("");
         // Remove downloaded files
        #if (CC_TARGET_PLATFORM != CC_PLATFORM_WIN32)
         string command = "rm -r ";
         // Path may include space.
         command += "\"" + _pathToSave + "\"";
         system(command.c_str());
        #else
         std::string command = "rd /s /q ";
         // Path may include space.
         command += "\"" + _pathToSave + "\"";
         system(command.c_str());
        #endif
         getAssetManager()->deleteVersion();
         initDownloadDir();
        }
        
        void Upgrade::upgrade(Ref* pSender)
        {
         _showDownloadInfo->setString("");
         getAssetManager()->update();
        
        }
         
         
        运行： 
           
        Reset：重置版本号，办删除下载资源。 
        Upgrad：校验版本号，当有更新时下载新资源。 
           
        _pathToSave保存着文件的下载路径，压缩包下载下来后，将被自动解压到_pathToSave中。 
        以win32为，在cocos2d-x\build\Debug.win32\ 中，可以看到我们之前设置的下载目录download。 
        onSuccess中，当下载成功后，将跳转到HelloWorld。  
        这时可以在HelloWorld中直接使用已下载的资源。