Question

having a look at the following code:

    CCSprite* testsprite = [CCSprite spriteWithFile:@"test.png"];
    CCLOG(@"1. count: %d", [testsprite retainCount]);
    [self addChild:testsprite];
    CCLOG(@"2. count: %d", [testsprite retainCount]);
    [testsprite runAction: [CCMoveTo actionWithDuration:3.0 position:CGPointMake(200.0, 200.0)]];
    CCLOG(@"3. count: %d", [testsprite retainCount]);

the output of this code is:

1. count: 1
2. count: 2
3. count: 3

I think I understand what happens here. The question is the following: is there a rule of thumb when (in which methods) Cocos2D retains objects (in this case testsprite)?

Bye, Christian

Answer 1

1. If possible use the class functions because they are autoreleased.
2. Adding a CCNode with addChild will retain the node. If you did some alloc init stuff, release it after adding it as a child
3. Adding anything to an array retains the object. You can safely release an object if you added it to an array.

autoreleased:

CCSprite *sprite = [CCSprite spriteWithFile:@"icon.png"];

manual memory management

CCSprite *sprite = [[CCSprite alloc] initWithFile:@"icon.png"];

Dont let the retainCount confuse you. Each line of code will maybe retain the object. If it is done well, the underlying code will release it automatically after it is finished.

A common example when you have to type release.

NSMutableArray *units = [NSMutableArray array];
for (int i = 0; i < 42; i++)
{
    CCNode *unit = [[MyUnit alloc] init]; // retain +1
    [units addObject:unit]; // retain +1
    [unit release]; // retain -1
}