detect collision with sprite in sprite sheet - iphone

Question

I have a sprite sheet in which there a four images(bat1,bat2,bat3.bat4) , in Image there is a person with holding the bat and when all images are combined in animation then it looks like playing baseball.
below is the code that i have used to add sprite sheet.
[[CCSpriteFrameCache sharedSpriteFrameCache] addSpriteFramesWithFile:#"baseball.plist"];
spriteSheet = [CCSpriteBatchNode batchNodeWithFile:#"baseball.plist"];
[self addChild:spriteSheet];
background = [CCSprite spriteWithSpriteFrameName:#"bat4.png"];
background.position = ccp(220, 185);
background.tag = 10;
[self addChild:background];
for(int i = 1; i < 5; i++) {
[walkAnimFrames addObject:[[CCSpriteFrameCache sharedSpriteFrameCache] spriteFrameByName:[NSString stringWithFormat:#"bat%d.png", i]]];
}
CCAnimation *walkAnim = [CCAnimation animationWithSpriteFrames:walkAnimFrames delay:5.0f];
self.walkAction = [CCRepeatForever actionWithAction:[CCAnimate actionWithAnimation:walkAnim]];
[background runAction:_walkAction];
And i am detecting the collision of ball with bat. by below code
for (CCSprite *monster in _monsters) {
if (CGRectIntersectsRect(background.boundingBox, monster.boundingBox)) {
if (((background.position.x -5 > monster.position.x + (monster.contentSize.width/2)) && background.position.y > monster.position.y)) {
isCollision = 1;
[monstersToDelete addObject:monster];
}
// [monstersToDelete addObject:monster];
//[self addFishToBoat];
}
}
here wat happen is collision is detected but it always detect collision with rect of bat4.. as the bat is moving and the cgrect of all bat is different so even when bas is very much far away from bat1 then it will detect the collision because ball's rect will intersect with rect of bat4.
But i want the collision will de detect only when the ball will collide wiith different bats, i mean when bal hit with bat1,bat2,bat3,bat4 then only it will detect the collision rather then detect with bat4 always

Answer 1

Here is great tutorials by raywenderlich on sprites collision detection.
Or
You can try this tutorial also Sprite Collision
Hope these will help you.

Answer 2

You try this code it may help you...
_contactListener = new MyContactListener();
_world->SetContactListener(_contactListener);
// Preload effect
[[SimpleAudioEngine sharedEngine] preloadEffect:#"hahaha.caf"];
std::vector<b2Body *>toDestroy;
std::vector<MyContact>::iterator pos;
for(pos = _contactListener->_contacts.begin();
pos != _contactListener->_contacts.end(); ++pos) {
MyContact contact = *pos;
b2Body *bodyA = contact.fixtureA->GetBody();
b2Body *bodyB = contact.fixtureB->GetBody();
if (bodyA->GetUserData() != NULL && bodyB->GetUserData() != NULL) {
CCSprite *spriteA = (CCSprite *) bodyA->GetUserData();
CCSprite *spriteB = (CCSprite *) bodyB->GetUserData();
if (spriteA.tag == 1 && spriteB.tag == 2) {
toDestroy.push_back(bodyA);
} else if (spriteA.tag == 2 && spriteB.tag == 1) {
toDestroy.push_back(bodyB);
}
}
}
std::vector<b2Body *>::iterator pos2;
for(pos2 = toDestroy.begin(); pos2 != toDestroy.end(); ++pos2) {
b2Body *body = *pos2;
if (body->GetUserData() != NULL) {
CCSprite *sprite = (CCSprite *) body->GetUserData();
[_spriteSheet removeChild:sprite cleanup:YES];
}
_world->DestroyBody(body);
}
if (toDestroy.size() > 0) {
[[SimpleAudioEngine sharedEngine] playEffect:#"hahaha.caf"];
}
Fore more detail about this code visit
http://www.raywenderlich.com/606/how-to-use-box2d-for-just-collision-detection-with-cocos2d-iphone