CCArray problem use lua

cocos2d-x Lua
#1

When I use a CCArray,and I add a CCString object. But When I get the object use ObjectInIndex.I will get a CCObject,not CCString. How I solve this problem. Rewrite the ObjectInIndex? Can you help me?

#2

@
local str = arr:objectAtIndex(0)
str = tolua.cast (str, “CCString”)
@

#3

OK Thanke you very much.