Box2d Cocos2d ContactListener detecting collision -

my problem simple, can't fix it.

i have radar rotating , have player moving joystick

well, want detect collision between radar , player. works when both moving doesn't when radar moving , player not.

here have code detect , how works:

//moves radar     [self schedule:@selector(loopradar) interval: 12];  //moves player joystick     body->setlinearvelocity(b2vec2(scaledvelocity.x*dt, scaledvelocity.y*dt));     actor.position = ccp(body->getposition().x * ptm_ratio,                          body->getposition().y * ptm_ratio);  // detects collision between radar , player     std::vector<mycontact>::iterator pos;     for(pos = _contactlistener->_contacts.begin();         pos != _contactlistener->_contacts.end(); ++pos) {         mycontact contact = *pos;            if ((contact.fixturea == radarbody->getfixturelist() && contact.fixtureb == body->getfixturelist()) ||             (contact.fixturea == body->getfixturelist() && contact.fixtureb == radarbody->getfixturelist())) {              //do game on            }      } //ends collision 

mycontactlistener class:

#import "mycontactlistener.h"  mycontactlistener::mycontactlistener() : _contacts() {  }   mycontactlistener::~mycontactlistener() {  }  void mycontactlistener::begincontact(b2contact* contact) { // need copy out data because b2contact passed in // reused. mycontact mycontact = { contact->getfixturea(), contact->getfixtureb() }; _contacts.push_back(mycontact); }  void mycontactlistener::endcontact(b2contact* contact) { mycontact mycontact = { contact->getfixturea(), contact->getfixtureb() }; std::vector<mycontact>::iterator pos; pos = std::find(_contacts.begin(), _contacts.end(), mycontact); if (pos != _contacts.end()) {     _contacts.erase(pos); } }  void mycontactlistener::presolve(b2contact* contact,                              const b2manifold* oldmanifold) { }  void mycontactlistener::postsolve(b2contact* contact,                               const b2contactimpulse* impulse) { } 

so, problem when radar goes through player , player isn't moving, doesn't detect collision, when both moving works perfectly.

any tips? thank much!

worked adding these lines "learncocos2d" said, setting both bodies awake

    body->setawake(true);     radarbody->setawake(true); 

thank much!