cocos2d iphone - body null when accessed from another method -


i have contact listener handles contact between 2 box2d bodies. accessing bodies contacter in helloworldlayer since box2d recommends contacting bodies should saved , changes implemented after timestep. please see code below:

contacter.h:

#import "ccphysicssprite.h"  @interface contacter : ccphysicssprite {  }  @property(nonatomic, assign) nsmutablearray* arrayofbodies; @property(nonatomic, assign) ccphysicssprite* spritetodestroy;   -(void)physicsspritescontact:(ccphysicssprite*)onephysicssprite othersprite:(ccphysicssprite*)twophysicssprite;  @end

contacter.mm:

#import "contacter.h" #import "box2d.h"  @implementation contacter  @synthesize arrayofbodies = _arrayofbodies; @synthesize spritetodestroy = _spritetodestroy;  -(void)destroybodies:(b2body*)body   {     _arrayofbodies = [[nsmutablearray alloc] init];     nsvalue *bodyvalue = [nsvalue valuewithpointer:body];     [_arrayofbodies addobject:bodyvalue]; }  -(void)physicsspritescontact:(ccphysicssprite*)onephysicssprite othersprite:   (ccphysicssprite*)twophysicssprite; { int firsttag = onephysicssprite.tag; int secondtag = twophysicssprite.tag;  if (((firsttag == 90) && (secondtag == 101 )) || ((firsttag == 101) && (secondtag == 90))) {      if (tag1 == 90) {         [self destroybodies:onephysicssprite.b2body];// adds body array destroyed         spritetodestroy = onephysicssprite; // taking note of sprite destroyed      }     else if (tag2 == 90)   {         [self destroybodies:twophysicssprite.b2body];         spritetodestroy = twophysicssprite;     } }

}

the following method within helloworldlayer.mm called in update method:

-(void)removedestroyedbodiesandsprites  { bodycontact = [contacter node];     if ([bodycontact arrayofbodies]) {   (nsvalue* bodyvalue in [bodycontact arrayofbodies]) {     b2body *removebody;     removebody = (b2body*)[bodyvalue pointervalue];      world->destroybody(removebody);     removebody = null;     [self removechild:[bodycontact spritetodestroy]];        }     } }

there contact sprite not removed , body not destroyed in removedestroyedbodiesandsprites. after testing cclog found loop not satisfied meaning arrayofbodies null. surprising since contact established. appreciate assistance.

updated

below contact listener:

testcontactlistener.h:

#import <foundation/foundation.h> #import "cocos2d.h" #import "box2d.h" #import "gameobjects.h" #import "contacter.h"   class testcontactlistener : public b2contactlistener    { public:     contacter* contacter;      void begincontact(b2contact* contact); };

testcontactlistener.mm:

#import "testcontactlistener.h"  void testcontactlistener:: begincontact(b2contact *contact) {     contacter = [contacter node];      b2fixture       *fixturea = contact->getfixturea();     b2fixture       *fixtureb = contact->getfixtureb();     b2body          *fixtureabody = fixturea->getbody();     b2body          *fixturebbody = fixtureb->getbody();      ccphysicssprite* physicssprite = (ccphysicssprite*)fixtureabody->getuserdata();     ccphysicssprite* physicssprite2 = (ccphysicssprite*)fixturebbody->getuserdata();      [contacter physicsspritescontact:physicssprite othersprite:physicssprite2];  }

move destroybodies method init method, called once:

_arrayofbodies = [[nsmutablearray alloc] init];

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