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cocos2dx tolua传递参数分析：
tolua_Cocos2d_CCNode_addChild00 == void CCNode::addChild(CCNode *child)
tolua_Cocos2d_CCNode_addChild01 == void CCNode::addChild(CCNode *child, int zOrder)
tolua_Cocos2d_CCNode_addChild02 == void CCNode::addChild(CCNode *child, int zOrder, int tag)
上面是使用tolua把C++转到lua，上面三个分别对应不同的参数个数。我们这里分析一下最后一个：
/* method: addChild of class CCNode */
#ifndef TOLUA_DISABLE_tolua_Cocos2d_CCNode_addChild02
static int tolua_Cocos2d_CCNode_addChild02(lua_State* tolua_S)
{
tolua_Error tolua_err;
//这里判断参数是否合法，只能判断参数类型是否合法，如果参数类型检查不通过，就会报错
if (
!tolua_isusertype(tolua_S,1,"CCNode",0,&tolua_err) ||
!tolua_isusertype(tolua_S,2,"CCNode",0,&tolua_err) ||
!tolua_isnumber(tolua_S,3,0,&tolua_err) ||
!tolua_isnumber(tolua_S,4,0,&tolua_err) ||
!tolua_isnoobj(tolua_S,5,&tolua_err)
)
goto tolua_lerror;
else
{
//例如：middleBg:addChild(testSprite, Z_ORDER_1, 200)
//我们传递进来的参数和下面的一一对应
//这里可以清楚的看到传入参数的次序，第一是middleBg ...
CCNode* self = (CCNode*) tolua_tousertype(tolua_S,1,0); -- middleBg -- 1
CCNode* child = ((CCNode*) tolua_tousertype(tolua_S,2,0)); -- testSprite -- 2
int zOrder = ((int) tolua_tonumber(tolua_S,3,0)); -- Z_ORDER_1 -- 3
int tag = ((int) tolua_tonumber(tolua_S,4,0)); -- 200 -- 4
#ifndef TOLUA_RELEASE
if (!self) tolua_error(tolua_S,"invalid 'self' in function 'addChild'", NULL);
#endif
{
//这里就把testSprite加到了middleBg
self->addChild(child,zOrder,tag);
}
}
return 0;
tolua_lerror:
return tolua_Cocos2d_CCNode_addChild01(tolua_S);
}
#endif //#ifndef TOLUA_DISABLE
例子：
//middleBg:addChild(testSprite, Z_ORDER_1, 200) 在传递参数中，我们没有对Z_ORDER_1赋值，即为nil，则就
//出现了下面的错误，看下这里argument #3 ，表明是第三个参数错误，而这里我们明明是第二个参数，看下上面的分析
//我想大家应该明白了，通过这种方法，我们以后查找这类问题，就会方便很多。
03-31 10:09:50.499: D/cocos2d-x debug info(3169): LUA ERROR: [string "xxxxxxxxxxxxx..."]:171: error in function 'addChild'.
03-31 10:09:50.499: D/cocos2d-x debug info(3169): argument #3 is 'nil'; '[no object]' expected.
03-31 10:09:50.499: D/cocos2d-x debug info(3169): stack traceback:
03-31 10:09:50.499: D/cocos2d-x debug info(3169): [C]: in function 'addChild'
03-31 10:09:50.499: D/cocos2d-x debug info(3169): [string "xxxxxxxxxxxxx..."]:171: in function 'initMiddle'
03-31 10:09:50.499: D/cocos2d-x debug info(3169): [string "xxxxxxxxxxxxx..."]:35: in function 'initUI'
03-31 10:09:50.499: D/cocos2d-x debug info(3169): [string "xxxxxxxxxxxxx..."]:27: in function 'ctor'
03-31 10:09:50.499: D/cocos2d-x debug info(3169): [string "xxxxxxxxxxxxx"]:34: in function 'create'
03-31 10:09:50.499: D/cocos2d-x debug info(3169): [string "xxxxxxxxxxxxx"]:38: in function 'new'
03-31 10:09:50.499: D/cocos2d-x debug info(3169): [string "xxxxxxxxxxxxx"]:44: in function 'pushScene'
03-31 10:09:50.499: D/cocos2d-x debug info(3169): [string "xxxxxxxxxxxxx"]:309: in function 'callBack'
03-31 10:09:50.499: D/cocos2d-x debug info(3169): [string "xxxxxxxxxxxxx"]:653: in function <[string "xxxxxxxxxxxxx"]:651>
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原文地址：http://blog.csdn.net/tianxiawuzhei/article/details/44775595
