Set TableView Cell image from AFNetworking download

Question

I'm using AFNetworking to download rss feed image set to table view. Following is the code I'm using.

- (UITableViewCell *)tableView:(UITableview *)tableView cellForItemAtIndexPath:(NSIndexPath *)indexPath;
{
    Cell *cell = [cv dequeueReusableCellWithReuseIdentifier:@"MY_CELL" forIndexPath:indexPath];

    NSString *wallpaperLink = [af setThumbString:[[feeds objectAtIndex:indexPath.row] objectForKey: @"wallpaper"]];

    //AfNetwork Download
    AFHTTPRequestOperation *requestOperation = [[AFHTTPRequestOperation alloc] initWithRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:wallpaperLink]]];
    requestOperation.responseSerializer = [AFImageResponseSerializer serializer];
    [requestOperation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
       //Set Cell Image from response
       cell.imageView.image = responseObject;
    } failure:^(AFHTTPRequestOperation *operation, NSError *error) {
        NSLog(@"Image error: %@", error);
    }];
    [requestOperation start];

    return cell;
}

But when I go through some tutorials I realise that this is not the way to download asynchronous images with AFNetworking. Can someone tell me for my code, how to download & add the responseobject to cell.imageView.image ???

Answer 1

I do it that way to avoid memory leaks:

NSURL *url = [NSURL URLWithString:@"http:url..."];
NSURLRequest *request = [NSURLRequest requestWithURL:url];
UIImage *placeholderImage = [UIImage imageNamed:@"your_placeholder"];

__weak UITableViewCell *weakCell = cell;

[cell.imageView setImageWithURLRequest:request
                      placeholderImage:placeholderImage
                               success:^(NSURLRequest *request, NSHTTPURLResponse *response, UIImage *image) {

                                   weakCell.imageView.image = image;
                                   [weakCell setNeedsLayout];

                               } failure:nil];

It works fine with AFNetworking 2.

As @Greg suggest in a comment: You have to add #import "UIImageView+AFNetworking.h".

Answer 2

If you are using AFNetworking, why not use the UIImageView+AFNetworking category? Just import UIImageView+AFNetworking.h and use this method:

- (void)setImageWithURLRequest:(NSURLRequest *)urlRequest
              placeholderImage:(UIImage *)placeholderImage
                       success:(void (^)(NSURLRequest *request, NSHTTPURLResponse *response, UIImage *image))success
                       failure:(void (^)(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error))failure;

Edit: Don't forget to call setNeedsLayout on the cell after you set the image!

Answer 3

When you are doing asynchronous image downloading, you can't get the result image on UITableViewCell immediately. So, You should download the images and show them using array of downloaded image as per tableView indexPath.

Please refer this link to download image using lazy-loading and display it in UITableViewCell.

Thanks!