cocoslua 使用addCustomHandler传递函数作为参数 到C++

在C++中写的方法，如果需要传递函数，当绑定到lua时，genbinding.py生成的绑定类会直接return 0,是的lua无法设置回调函数，但是widget子类，如button,sprite确能设置点击事件，触摸事件，所以我看了下cocos2dx自己的绑定方式，发现用的是ScriptHandlerMgr::getInstance()->addCustomHandler方法实现，如此，我们就直接拿来用吧

核心代码只有几行

1 hpp,cpp

#ifndef SDKManager_h
#define SDKManager_h

#include"cocos2d.h"

typedef std::function<void(int ,std::string)> sdkCallFunc;
class SDKManager    {
    SDKManager(){};
    ~SDKManager(){};
    
private:
    sdkCallFunc sdkCallfunc;
public:
    static SDKManager* getInstance();
    
    int test(int number);
    void setCallback(const sdkCallFunc& callfunc);  

};


#endif /* SDKManager_h */

#include "SDKManager.hpp"

#include "scripting/lua-bindings/manual/CCLuaEngine.h"
SDKManager* g_instance = nullptr;
SDKManager* SDKManager::getInstance()
{
    if (g_instance == nullptr) {
        g_instance = new SDKManager();
    }
    
    return g_instance;
    
}

int SDKManager::test(int v)
{
    if (this->sdkCallfunc) {
        this->sdkCallfunc(v,"setcallback ==== ");
    }
    

    return v + 100;
}

2,修改生成的lua_sdkmanager_auto.cpp文件 

int lua_sdkmanager_SDKManager_setCallback(lua_State* tolua_S)
{
    ...
    ...
    argc = lua_gettop(tolua_S)-1;
    if (argc == 1) 
    {
        if(!toluafix_isfunction(tolua_S,2,"LUA_FUNCTION",0,&tolua_err))
        {
            goto tolua_lerror;
        }
        LUA_FUNCTION handler = (  toluafix_ref_function(tolua_S,2,0));
        
        cobj->setCallback([=](int eventType,const std::string& param1){
            LuaStack* stack = LuaEngine::getInstance()->getLuaStack();
            
            stack->pushInt((int)eventType);
            stack->pushString(param1.c_str());
            
            stack->executeFunctionByHandler(handler, 2);
            stack->clean();
        });
        
        ScriptHandlerMgr::getInstance()->addObjectHandler((void*)cobj, handler, ScriptHandlerMgr::HandlerType::EVENT_CUSTOM_BEGAN);
        return 0;
//        std::function<void (int, std::basic_string<char>)> arg0;
//
//        do {
//            // Lambda binding for lua is not supported.
//            assert(false);
//        } while(0)
//        ;
//        if(!ok)
//        {
//            tolua_error(tolua_S,"invalid arguments in function 'lua_sdkmanager_SDKManager_setCallback'", nullptr);
//            return 0;
//        }
//        cobj->setCallback(arg0);
//        lua_settop(tolua_S, 1);
//        return 1;
    }
    ...
    ...
}