Hi guys, i had a error pop up, can you help me?

Severity Code Description Project File Line Suppression State Error C3867 'GameScene::onContactBegin': non-standard syntax; use '&' to create a pointer to member Frogger

e:\users\ringo\appdata\local\android\cocos2d\frogger\classes\gamescene.cpp 58

which was this line down here contactListener->onContactBegin = CC_CALLACK_1(GameScene::onContactBegin, this);

Here is my code https://github.com/ringol5046/242​