Contact on physics scene not triggering

in init function my listener is;

auto contactListener = EventListenerPhysicsContact::create();
contactListener->onContactBegin = CC_CALLBACK_1(HelloWorld::onContactBegin, this);
this->_eventDispatcher->addEventListenerWithSceneGraphPriority(contactListener, this);

bool HelloWorld::onContactBegin(PhysicsContact& contact) {
    CCLOG("Something Contact: %f", 1);
    return true;
}

build works without error but onContactBegin not triggered when contact occoured. I tried with lamba function version but not triggering

solved by setting contact test number for both PhysicsBodies to be tested;

sprite->getPhysicsBody()->setContactTestBitmask(10);