Beware of [self init]

In a new app I’m working on, I created a series of lightweight cocos2d sprite subclasses which simply call the superclass init with some parameters. As soon as I called it I ended up crashing with a weird looking stack trace showing lots of nested calls to init methods.

Screen shot 2011-03-06 at 2.18.44 PM.png

My init methods were pretty simple:


@implementation Gummybear

-(id)init {
    return [super initWithName: @"gummybear.png"];
}

@end

My superclass’s init method used CCSprite’s initWithSpriteFrameName: method.


- (id)initWithName: (NSString*)name
{
    self = [super initWithSpriteFrameName:name];
    if (nil != self) {
		// do some more initialization here
    }
    return self;
}

It ultimately ends up calling initWithTexture:, which is where the problem lies. It turns out initWithTexture: is calling [self init]. Guess which init method was getting called?


-(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]) )
	{
		[self setTexture:texture];
		[self setTextureRect:rect];
	}
	return self;
}

The fix was to simply change the name of my init method to something else.

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