Question

I have cocos2d project with custom CCSprite subclass:

MyCustomSprite.h:

#import "cocos2d.h"
@interface MyCustomSprite : CCSprite
@end

MyCustomSprite.m:

#import "MyCustomSprite.h"
@implementation MyCustomSprite
- (id)init
{
    self = [super initWithFile:@"index.png"];
    return self;
}
@end

For some strange reason, this code will crash with “EXC_BAD_ACCESS”.

But in spite of this, if i init super as ususal and then write code from CCSprite’s initWithFile and initWithTexture, it will work fine:

self = [super init];
if (self) {
    // Code from CCSprite.m - initWithFile
    CCTexture2D *texture = [[CCTextureCache sharedTextureCache] addImage: @"index.png"];
    CGRect rect = CGRectZero;
    rect.size = texture.contentSize;

    // Code from CCSprite.m - iniWithTexture
    [self setTexture:texture];
    [self setTextureRect:rect];

    return self;
} 

What’s the reason that the first example crashes, and second not and what’s the difference between them?

Thanks for your answers!

Answer 1

Ok, the reason is bad CCSprite design. If we look to CCSprite.h, we can find:

-(id) initWithTexture:(CCTexture2D*)texture rect:(CGRect)rect
{
    NSAssert(texture!=nil, @"Invalid texture for sprite");
    // IMPORTANT: [self init] and not [super init];
    if( (self = [self init]) )
}

And thats the reason. Instead of [super init] this method calls [self init], and creates recursion ([self init]-[super InitWithFile:]-[self initWithTexture]-[self init]-...).

.

So, the simplest way to solve this problem – just re-name your init method to something else (for example “initialize”) and call it instead of init: [[MyCustomSprite
alloc] initialize].