TableViewCell ImageView shows always different data

Question

I have a chat and want to display the users profile pictures. Everything will be displayed correctly but not the profile pictures of the users. Everytime, when I reload my view, I get other pictures.

I load the Profileimage in with the following lines:

func showProfilImage(uid: String, completion: @escaping (UIImage) -> Void) {
    UserApi.shared.observeUser(uid: uid) { (user) in
        guard let url = URL(string: user.profilImageUrl!) else { return }

        URLSession.shared.dataTask(with: url) { (data, response, error) in
            guard error == nil, let data = data, let image = UIImage(data: data) else { return }
                DispatchQueue.main.async {
                    let finishedImage = image.withRenderingMode(.alwaysOriginal)
                    completion(finishedImage)
                }
                }.resume()
    }
}

Then I call showProfilImage in cellForRowAt with the following lines:

self.showProfilImage(uid: self.items[indexPath.row].user.uid!) { (image) in
    cell.profilePic.image = image
}

UPDATE

Now i implemented sdWebImage and make a completion with the URL:

func showProfilImage(uid: String, completion: @escaping (URL) -> Void) {
    UserApi.shared.observeUser(uid: uid) { (user) in
        guard let url = URL(string: user.profilImageUrl!) else { return }
        completion(url)
    }
}

Here I call my showProfilImage:

self.showProfilImage(uid: self.items[indexPath.row].user.uid!) { (url) in
            cell.profilePic.image = nil
            cell.profilePic.sd_setImage(with: url, completed: { (_, _, _, _) in
            })
        }

user_5820010 · Answer

Your current code has dequeuing and no cashing problems and the right for that is to use SDWebImage

cell.profilePic.sd_setImage(with: URL(string:urlStr), placeholderImage: UIImage(named: "placeholder.png"))

also something like

UserApi.shared.observeUser(uid: uid) { (user) in

would be once say in viewDidLoad

user_8192960 · Answer

If you're fetching the image correctly for each user then you problem might be laying in scrolling and dequeuing the cell to solve such issue inside the UITableViewCell custom class use this function to clear out the UIImageView each time a dequeue happens.

override func prepareForReuse() {
        super.prepareForReuse()
        self.imageView.image = nil  //setting the image to nil  when get dequeued to reuse 
    }

TableViewCell ImageView shows always different data

3 Answers