WeakSelf;
[SDWebImageDownloader.sharedDownloader downloadImageWithURL:url options:SDWebImageDownloaderHandleCookies progress:^(NSInteger receivedSize, NSInteger expectedSize)
{
// progression tracking code
}completed:^(UIImage *image, NSData *data, NSError *error, BOOL finished){
dispatch_async(dispatch_get_main_queue(), ^{
if (image && finished)
{
weakSelf.headImage.image = image;
}
});
}];