Subclass CCSprite and error "undefined reference to `vtable for MySprite'"

cocos2d-x C++
#1

I create subclass MySprite from CCSPrite:
MySprite.h:
#include “cocos2d.h”

class MySprite: public cocos2d::CCSprite {
public:
MySprite():cocos2d::CCSprite(){};
virtual void draw();

};

MeSprite.cpp:
#include “MySprite.h”

void MySprite::draw() {
glAlphaFunc(GL_GREATER, 0.7);
glEnable (GL_ALPHA_TEST);
CCSprite::draw();
glDisable(GL_ALPHA_TEST);
}

In main class i do:
MySprite* mySpr = new MySprite();
mySpr~~>setTexture~~>getTexture);
mySpr~~>setPosition);
this~~>addChild(mySpr);

and take error: undefined reference to `vtable for MySprite’
What i do wrong?

#2

hi:
i met this problem before.
try this way:
find the Android.mk file in /proj.android/jni
then add code like this
LOCAL_SRC_FILES := hellocpp/main.cpp \ ../../Classes/AppDelegate.cpp \ ../../Classes/HelloWorldScene.cpp \ ../../Classes/MySprite.cpp
gl , hf