I have an AssetInfo object which I use to encapsulate basic info about an ALAsset or other asset type that I may have in my app.
An asset info keeps the [alAsset thumbnail] as a CGImageRef. When I am checking in instruments I appear to have twice as many CGImage objects than I should. Say there are 4000 AssetInfo instances, I will have about 8000 CGImage instances.
I am instantiating my AssetInfo object as below.
- (void)enumerateAsset:(AssetsGroupInfo *)assetsGroup alAsset:(ALAsset *)alAsset withIndex:(NSUInteger)index {
NSDate *date = [alAsset valueForProperty:ALAssetPropertyDate];
NSString *dateKey = [date dateKey];
CGImageRef thumbnail = [alAsset thumbnail];
NSURL *url = [[alAsset defaultRepresentation] url];
AssetInfo *alAssetInfo = [[AssetInfo alloc]
initWithURL:url
withDate:date
withThumbnail:thumbnail];
//...
}
My AssetInfo class looks like this
@implementation AssetInfo {
@private
NSDate *_dateCreated;
NSURL *_url;
CGImageRef _thumbnail;
}
- (id)initWithURL:(NSURL *)url withDate:(NSDate *)date withThumbnail:(CGImageRef)thumbnailRef {
if ((self = [self init])) {
_url = url;
_dateCreated = date;
_thumbnail = CGImageRetain(thumbnailRef);
}
return self;
}
- (NSURL *)url {
return _url;
}
- (NSDate *)dateCreated {
return _dateCreated;
}
- (CGImageRef)thumbnail {
return _thumbnail;
}
#pragma mark - Equality
- (BOOL)isEqual:(id)object {
//TODO:Include date in equality checking
BOOL valueToReturn = NO;
if (object && [object respondsToSelector:@selector(url)]) {
NSURL *myUrl = [self url];
NSURL *objURL = [object url];
valueToReturn = ([myUrl isEqualToURL:objURL]);
}
return valueToReturn;
}
- (NSUInteger)hash {
return [[self url] hash];
}
- (void)dealloc {
NSLog(@"%s", __PRETTY_FUNCTION__);
CGImageRelease(_thumbnail);
}
@end
I later use the asset as shown in the code below.
- (void)loadWithAsset:(AssetInfo *)asset {
_asset = asset;
_image = [[UIImage alloc] initWithCGImage:[_asset thumbnail]];
}
If I release the thumbnail at the point where I am instantiating the AssetInfo (as shown in snnippet below) the number of living CGImage objects corresponds to the number of living AssetInfo objects. however when I try to access the thumbnail property of the AssetInfo object the app crashes with a EXC_BAD_ACCESS at the line in the above code where I instantiate a UIImage with the CGImageRef.
- (void)enumerateAsset:(AssetsGroupInfo *)assetsGroup alAsset:(ALAsset *)alAsset withIndex:(NSUInteger)index {
NSDate *date = [alAsset valueForProperty:ALAssetPropertyDate];
NSString *dateKey = [date dateKey];
CGImageRef thumbnail = [alAsset thumbnail];
NSURL *url = [[alAsset defaultRepresentation] url];
AssetInfo *alAssetInfo = [[AssetInfo alloc]
initWithURL:url
withDate:date
withThumbnail:thumbnail];
//...
CGImageRelease(thumbnail);
}
Am I doing something wrong?
