LNK2019函數中未解析的外部符號引用

Question

在Visual Studio中運行的基本cocos2dx應用程序中獲取鏈接器錯誤。當AppDelegate的「applicationDidFinishLaunching」方法調用「MyGameScene」的「單例」方法時發生。 我已經檢查了在MyGameScene.h定義的方法MyGameScene.cpp類實現

錯誤味精

Error 1 error LNK2019: unresolved external symbol "public: static class 
MyGame * __cdecl MyGame::singleton(void)" (?singleton@MyGame@@SAPAV1@XZ) 
referenced in function "public: virtual bool __thiscall 
AppDelegate::applicationDidFinishLaunching(void)" 
(?applicationDidFinishLaunching@AppDelegate@@UAE_NXZ) D:\Dev\cocos2d-2.0-x- 
2.0.4\MyGame\proj.win32\AppDelegate.obj MyGame 

AppDelegate.h

#ifndef _APP_DELEGATE_H_ 
#define _APP_DELEGATE_H_ 

#include "CCApplication.h" 

/** 
@brief The cocos2d Application. 

The reason for implement as private inheritance is to hide some interface call by CCDirector. 
*/ 
class AppDelegate : private cocos2d::CCApplication 
{ 
public: 
AppDelegate(); 
virtual ~AppDelegate(); 

/** 
@brief Implement CCDirector and CCScene init code here. 
@return true Initialize success, app continue. 
@return false Initialize failed, app terminate. 
*/ 
virtual bool applicationDidFinishLaunching(); 

/** 
@brief The function be called when the application enter background 
@param the pointer of the application 
*/ 
virtual void applicationDidEnterBackground(); 

/** 
@brief The function be called when the application enter foreground 
@param the pointer of the application 
*/ 
virtual void applicationWillEnterForeground(); 
}; 

#endif // _APP_DELEGATE_H_ 

AppDelegate中。 cpp

#include "AppDelegate.h" 
#include "cocos2d.h" 
#include "MyGameScene.h" 

USING_NS_CC; 

AppDelegate::AppDelegate() 
{ 

} 

AppDelegate::~AppDelegate() 
{ 
} 

bool AppDelegate::applicationDidFinishLaunching() 
{ 
// initialize director 
CCDirector *pDirector = CCDirector::sharedDirector(); 
pDirector->setOpenGLView(CCEGLView::sharedOpenGLView()); 

// turn on display FPS 
pDirector->setDisplayStats(true); 

// set FPS. the default value is 1.0/60 if you don't call this 
pDirector->setAnimationInterval(1.0/60); 

// create a scene. it's an autorelease object 
MyGame *MyGame = MyGame::singleton(); 
CCScene *pScene = MyGame->scene(); 

// run 
pDirector->runWithScene(pScene); 

return true; 
} 

// This function will be called when the app is inactive. When comes a phone call,it's be invoked too 
void AppDelegate::applicationDidEnterBackground() 
{ 

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

// if you use SimpleAudioEngine, it must be pause 
// SimpleAudioEngine::sharedEngine()->pauseBackgroundMusic(); 
} 

// this function will be called when the app is active again 
void AppDelegate::applicationWillEnterForeground() 
{ 

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

// if you use SimpleAudioEngine, it must resume here 
// SimpleAudioEngine::sharedEngine()->resumeBackgroundMusic(); 
} 

MyGameScene.h

#ifndef __MYGAME_SCENE_H__ 
#define __MYGAME_SCENE_H__ 

#include "cocos2d.h" 
#include "Box2D/Box2d.h" 

#define PTM_RATIO 32 

USING_NS_CC; 
class MyGame: public cocos2d::CCLayer { 
public: 

    cocos2d::CCSprite *_ball; 

    // implement the "static node()" method manually 
    CREATE_FUNC(MyGame) 
    ; 

    static MyGame *singleton(); 

    MyGame(); 
    ~MyGame(); 

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

    // there's no 'id' in cpp, so we recommand to return the exactly class pointer 
    cocos2d::CCScene* scene(); 

    // a selector callback 
    void menuCloseCallback(CCObject* pSender); 

    void Tick(float dt); 

private: 
    CCScene *_scene; 

    int mWidth; 
    int mHeight; 

}; 

#endif // __MYGAME_SCENE_H__ 

MyGameScene.cpp

#include "MyGameScene.h" 
//#include "SimpleAudioEngine.h" 
#include "Shaders.h" 

using namespace cocos2d; 
//using namespace CocosDenshion; 

#define COCOS2D_DEBUG 1 

extern "C" { 
#include <pthread.h> 
#include <unistd.h> 
} 

static MyGame *_MyGameSingleton = NULL; 
static bool mIsNewFrameReceived; 

MyGame* MyGame::singleton() { 
    // 'layer' is an autorelease object 
    if (_MyGameSingleton == NULL) { 
     _MyGameSingleton = MyGame::create(); 

    } 
    return _MyGameSingleton; 
} 

CCScene* MyGame::scene() { 
    if (!_scene) { 
     // 'scene' is an autorelease object 
     _scene = CCScene::create(); 

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

    // return the scene 
    return _scene; 
} 

// on "init" you need to initialize your instance 
bool MyGame::init() { 
    _scene = NULL; 

    if (!CCLayer::init()) { 
     return false; 
    } 
// CCLOG("init"); 
// CCSize winSize = CCDirector::sharedDirector()->getWinSize(); 
// mWidth = winSize.width; 
// mHeight = winSize.height; 
    this->schedule(schedule_selector(MyGame::Tick)); 

    return true; 
} 

void MyGame::menuCloseCallback(CCObject* pSender) { 
    CCDirector::sharedDirector()->end(); 

#if (CC_TARGET_PLATFORM == CC_PLATFORM_IOS) 
    exit(0); 
#endif 
} 

MyGame::~MyGame() { 

} 


MyGame::MyGame() { 

} 

void MyGame::Tick(float dt) { 
    CCDirector *director = CCDirector::sharedDirector(); 
    CCSize windowSize = director->getVisibleSize(); 
    mWidth = windowSize.width; 
    mHeight = windowSize.height; 
} 

UPDATE 我在Visual Studio本身的項目中創建一個新的類，並複製所有的變量以及MyGame類的成員函數。然後，我能夠引用新的類並正確編譯。

[複製我的評論在這裏FYI] 我能夠使用cygwin在Windows上編譯現有的cocos2dx遊戲，我的同事能夠使用XCode在Mac上編譯相同的東西。這個問題只在使用Visual Studio進行編譯時纔有意義

我認爲Visual Studio沒有編譯MyGame文件。我怎樣才能確保課程將被編譯？

Answer 1

我發現從模板創建項目後，我沒有正確鏈接cocos2dx庫。這就是鏈接器錯誤的原因[雖然錯誤指向了不同的方向]。
謝謝大家的幫助！
我打算列出我以後使用的正確步驟，在Visual Studio 2012中的現有cocos2dx項目中創建一個win32項目，對於任何使用類似問題訪問此問題的人。

Answer 2

您是否嘗試在.cpp文件的頂部設置靜態MyGame var？

static MyGame *singleton(); 

如果未設置任何位置，則會生成此錯誤。

Answer 3

我想這是一個錯字。錯誤消息確實包含足夠的信息。 「市民：靜態----- class ---- MyGame * __cdecl ......」

MyGame *MyGame 

應該

MyGame *myGame 

在AppdDeleate.cpp