Swift 3 : URL Image makes UITableView scroll slow issue

Question

I have an extension to print image URL on UIImageView. But I think the problem is my tableView is so slow because of this extension. I think I need

Answer 1

For caching image in background & scroll faster use SDWebImage library

 imageView.sd_setImage(with: URL(string: "http://image.jpg"), placeholderImage: UIImage(named: "placeholder.png"))

https://github.com/rs/SDWebImage