Having trouble adding multiple physics objects in Xcode cocos2d - ios

Question

I'm new to cocos2d and objective-c. I know I'm missing something here, but I just can't find the solution. Hope someone can help....
My goal is to be able to click any of the sprites that I've placed on the screen. To start, I've put 2 sprites on the screen. (Each sprite is in the shape of a star).
The problem is, only the second sprite placed on the screen is clickable. My guess is that when I call addNewStar, it replaces _star with the latest star sprite, and takes the previous _star out of the physics node. I want all the stars I add to be in the physics node and be clickable. No clue how to do this.
Here is my code...hopefully someone can point out my mistake(s)!
#implementation MainScene {
CCSprite *_star;
CCPhysicsNode *_physicsNode;
CCNode *_ground;
CCLabelTTF *_scoreLabel;
BOOL _gameOver;
CCButton *_restartButton;
}
- (void)didLoadFromCCB {
self.userInteractionEnabled = TRUE;
[self addNewStar];
[self addNewStar];
// set collision txpe
_ground.physicsBody.collisionType = #"level";
// set this class as delegate
_physicsNode.collisionDelegate = self;
}
-(void)addNewStar {
//This successfully loads my star onto the screen
_star = (Star *)[CCBReader load:#"Star"];
_star.physicsBody.collisionGroup = #"starGroup";
_star.physicsBody.collisionType = #"star";
_star.position = ccp(200,300);
[_physicsNode addChild:_star];
}
-(BOOL)ccPhysicsCollisionBegin:(CCPhysicsCollisionPair *)pair star:(CCNode *)star level:(CCNode *)level {
[self gameOver];
return TRUE;
}
- (void)touchBegan:(UITouch *)touch withEvent:(UIEvent *)event {
float ranNum1 = (arc4random_uniform(10000));
float ranNum2 = (arc4random_uniform(10000));
float sideForce = ranNum1 - ranNum2;
if (!_gameOver) {
CGPoint touchLocation = [touch locationInNode:_physicsNode];
if(CGRectContainsPoint([_star boundingBox], touchLocation))
{
[_star.physicsBody applyImpulse:ccp(sideForce, 1000.f)];
[_star.physicsBody applyAngularImpulse:2500.f];
}
}
}
- (void)restart {
CCScene *scene = [CCBReader loadAsScene:#"MainScene"];
[[CCDirector sharedDirector] replaceScene:scene];
}
- (void)gameOver {
if (!_gameOver) {
_gameOver = TRUE;
_restartButton.visible = TRUE;
_star.rotation = 90.f;
_star.physicsBody.allowsRotation = FALSE;
[_star stopAllActions];
CCActionMoveBy *moveBy = [CCActionMoveBy actionWithDuration:0.2f position:ccp(-2, 2)];
CCActionInterval *reverseMovement = [moveBy reverse];
CCActionSequence *shakeSequence = [CCActionSequence actionWithArray:#[moveBy, reverseMovement]];
CCActionEaseBounce *bounce = [CCActionEaseBounce actionWithAction:shakeSequence];
[self runAction:bounce];
}
}
#end

Answer 1

You only have one pointer to one star. So when you test if the star was touched in your touches began method then of course only the second one would do anything since your sole pointer is only pointing at the most recently created star.
To answer your question, the simple approach you could take is to add each star to an NSArray. Then in your touches began method you can loop over the array and see which star was touched.
Example:
// Recommend using properties over i-vars
#property (nonatomic, strong) NSMutableArray* starList;
// In init or onEnter...
self.starList = [NSMutableArray array];
// Each time you create a new star...
Star* star = ...;
[self addChild:star];
[self.starList addObject:star];
// In your touches began...
- (void)touchBegan:(UITouch *)touch withEvent:(UIEvent *)event
{
...
for (Star* star in self.starList)
{
// If star is touched...
// ...add your impulses, etc
}
}

Answer 2

This is touchBegan from my project. Maybe you can change code little bit for your need. What you can see here? After getting location of touch code searching b2Body which was touched. In your example you need to search your _physicsNode for _child that was touched.
for(UITouch *touch in allTouches)
{
CGPoint location = [touch locationInView:touch.view];
location = [[CCDirector sharedDirector] convertToGL:location];
b2Vec2 worldLoc = b2Vec2(ptm(location.x), ptm(location.y));
// SEARCH YOUR CHILD FROM NODE HERE
for (b = world->GetBodyList(); b; b = b->GetNext())
{
if (b->GetType() == b2_dynamicBody)
if (b->IsBullet() == false)
{
for (b2Fixture *f = b->GetFixtureList(); f; f = f->GetNext())
{
// Hit!
if (f->TestPoint(worldLoc))
{
//do stuff
}
break;
}
}
}
}