iOS Block image return - ios

Question

So I am working on a project and I must use AFImageDownloader in order to download some images that we need to use in our project. I use the following code:
-(void) downloadImage:(NSURL*) url
{
AFHTTPSessionManager *sessionManager = [[AFHTTPSessionManager alloc] init];
AFImageDownloader *imgDownloader = [[AFImageDownloader alloc] initWithSessionManager:sessionManager downloadPrioritization:AFImageDownloadPrioritizationFIFO maximumActiveDownloads:1 imageCache:nil];
AFHTTPResponseSerializer *responseSerializer = [AFHTTPResponseSerializer serializer];
responseSerializer.acceptableContentTypes = [NSSet setWithObjects:#"application/json", #"text/json",#"binary/octet-stream",nil];
sessionManager.responseSerializer = responseSerializer;
NSURLRequest *req = [NSURLRequest requestWithURL:url];
[imgDownloader downloadImageForURLRequest:req success:^(NSURLRequest *request, NSHTTPURLResponse *response, UIImage *responseObject){
self.image = responseObject;
[self.delegate updateImageWithImage:self.image]; // ** CRASH **
} failure:^(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error){
NSLog(#"Error");
}];
}
The delegate is of course not nil and code of the updateImageWithImage is:
-(void) updateImageWithImage:(UIImage*) img {
self.image.image = img;
}
So basically when I try to get the UIImage I get it as a response and assign it to the UICollectionViewCell and it crashes! I guess that I should do some kind of "copy" of the responseObject before using it in order parts of my program, but I am not really sure what the problem is. Any ideas?

Answer 1

I figured it out. I was basically using AFImagedownloader wrong, this is the proper way to use this Class:
[self.imageView setImageWithURLRequest:jpegURLRequest
placeholderImage:placeholder
success:^(NSURLRequest *request, NSHTTPURLResponse * _Nullable response, UIImage *image){
NSLog(#"Success");
completionBlock(image);
}
failure:^(NSURLRequest * _Nonnull request, NSHTTPURLResponse * _Nullable response, NSError * _Nonnull error) {
NSLog(#"ERROR!!!");
}];