Question

I am loading a bunch of images using AFNetworking and I would like to scale and apply rounded corners to these images before AFNetworking caches them.

I started out scaling and applying rounded corners to the images each time they were loaded but the completion block will also be called when the image is loaded from the cache and therefore this uses too many resources when a user scrolls a collection view filled with images.

[self.imageView setImageWithURLRequest:[NSURLRequest requestWithURL:url
                                                        cachePolicy:NSURLRequestReturnCacheDataElseLoad
                                                    timeoutInterval:10.0f]
placeholderImage:kVideoCollectionViewCellVideoImagePlaceholder
success:^(NSURLRequest *request, NSHTTPURLResponse *response, UIImage *image) {
    /**
     * The image is edited here and this block is called
     * when the image is loaded from web and from the cache.
     */
    [self.imageView setImage:image];
}
failure:^(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error) {
    DDLogError(@"%@", error);
}];

AFNetworking seems to provide a great cache for my use, especially when I enable disk caching therefore I would like to use it but I can’t figure out if there’s a way to edit the image before it is cached.

Does anyone know if this is possible and if so, how it can be done?

Answer 1

After posting the question it hit me that I may have too look in another direction that using the UIImageView+AFNetworking category. Using the AFImageRequestOperation directly solved the problem.

__weak NZVideoCollectionViewCell *weakSelf = self;
NSURLRequest *request = [NSURLRequest requestWithURL:url
                                         cachePolicy:NSURLRequestReturnCacheDataElseLoad
                                     timeoutInterval:10.0f];
AFImageRequestOperation *operation = [AFImageRequestOperation imageRequestOperationWithRequest:request imageProcessingBlock:^UIImage*(UIImage *image) {
    /**
     *  Edit image.
     */
    return editedImage;
}
success:^(NSURLRequest *request, NSHTTPURLResponse *response, UIImage *image) {
    [weakSelf.imageView setImage:image];
}
failure:^(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error) {
    DDLogError(@"%@", error);
}];
[operation start];