array removeObjectsAtIndexes: - iphone

Question

I have a problem, with deleting items from an array..
first:
i have a variable of type int, called zan. in my HelloWordScene.h
int zan;
NSMutableArray * targets;
NSMutableArray *projectiles;
in my HelloWordScene.m. i have an object, animated:
-(id) init {
if((self = [super init])) {
[self schedule:#selector(update:)];
_targets = [[NSMutableArray alloc] init];
_projectiles = [[NSMutableArray alloc] init];
}
[self schedule:#selector(gameLogic:) interval:3];
return self;
}
in my selector I increment the var:
-(void)gameLogic:(ccTime)dt {
[self addTarget];
zan ++;
}
Later I have an animation and I have a addTarget:
// This loads an image of the same name (but ending in png), and goes through the
// plist to add definitions of each frame to the cache.
[[CCSpriteFrameCache sharedSpriteFrameCache] addSpriteFramesWithFile:#"zancudo.plist"];
// Create a sprite sheet with the images
CCSpriteBatchNode *spriteSheet = [CCSpriteBatchNode batchNodeWithFile:#"zancudo.png"];
[self addChild:spriteSheet];
// Load up the frames of our animation
NSMutableArray *walkAnimFrames = [NSMutableArray array];
for(int i = 0; i <= 4; ++i) {
[walkAnimFrames addObject:[[CCSpriteFrameCache sharedSpriteFrameCache] spriteFrameByName:[NSString stringWithFormat:#"zancu000%d.png", i]]];
}
CCAnimation *walkAnim = [CCAnimation animationWithFrames:walkAnimFrames delay:0.1f];
// Create a sprite for our bear
CGSize winSize = [CCDirector sharedDirector].winSize;
self.bear = [CCSprite spriteWithSpriteFrameName:#"zancu0001.png"];
//random position
int minY = _bear.contentSize.width/2;
int maxY = winSize.width - _bear.contentSize.width/2;
int rangeY = maxY - minY;
int actualX = (arc4random() % rangeY) + minY;
// Create the target slightly off-screen along the right edge,
// and along a random position along the Y axis as calculated above
_bear.position = ccp(actualX,winSize.height + (_bear.contentSize.height/2));
self.walkAction = [CCRepeatForever actionWithAction:[CCAnimate actionWithAnimation:walkAnim restoreOriginalFrame:NO]];
//animation
[spriteSheet addChild:_bear];
//∫aqui pasar un for para poder saber que position es
CCLOG(#"cantidad de zancudos%d",zan);
[_targets insertObject:_bear atIndex:zan];
i have deleted a mutable _target for index- i have a selector update. try delete a mutablearray this.
for (CCSprite *target in targetsToDelete) {
if (_targets.count!=0) {
for (int j=1; j==_targets.count; j++) {
[_targets removeObjectAtIndex:j];
}
}
I need help

Answer 1

use syntax like this for crash free delete;
NSArray *array = [NSArray arrayWithArray: _targets];
for(CCSprite *sprite in array)
{
if(sprite.tag == kToDelete) //mark somewhere in game :or use ur logic here
{
[_targets removeObject: sprite];
[sprite stopAllActions];
[sprite removeFromParentAndCleanup:YES];
}
}

Answer 2

Your loop will try and access an index out of the array's bounds...try this
for (int j = 0; j == _targets.count - 1; j++)
{
[_targets removeObjectAtIndex:j];
}
However, since it appears you are only removing the last element of the array with this code, you could skip the for loop and use:
[_targets removeLastObject];

Answer 3

The moment you remove an object from _targets, the effective count actually changes. So if you start the loop with a count of 10, and eventually the value of j will be out of bounds. I dont follow quite well the logic of your if ( the == ), but if you are trying to remove all objects, instead of the loop :
[_targets removeAllObjects];