How do I return a variable from a block inside a method?

Question

Say I have this method that given a URL returns a UIImage:

- (void)getUIImageFromURL:(NSURL *)URL {
    NSURLRequest *request = [NSURLRequest requestWithURL:         


        

Answer 1

The callback block in setCompletionBlockWithSuccess: is a void block, you can't change it's return type.

In your case, you would probably set the image inside of your block, instead of returning an image.

[imageOperation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
    self.myImage.image = [UIImage imageWithData:responseObject];
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
}];

However, if you are dealing with AFNetworking and images, there are category methods that should greatly simplify retrieval and cacheing.

[self.myImage setImagewithURL:URL];