Dynamic Uiimageview Size Within Uitableview

Change height of UIImageview dynamically

Since you're using auto-layout constraints you need to update height constraint not image view frame. So connect your height constraint as an IBOutlet heightConstraint in your tableViewCell. And then in table view cellForRowAt you have to set cell.heightConstraint.constant = image_height. And this will give you the desired result.

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
   // don't forget to dequeue your table view cell here
   //change height of UIImageView
   let image_height = image_width * CGFloat(viewModel.imageScale)
   cell.heightConstraint.constant = image_height
   //load image
   _ = homeViewCell.mainImageView.af_setImage(withURL: URL(string: serverURL + viewModel.mainImage)!, placeholderImage: UIImage(named : "home_placeholder") ...
}

Dynamic size of UIImageView inside UITableViewCell

The problem was that I was downloading the images from the web when the cells were being initiated and again when they were being reused.

Donwloading the cells content only once and storing them solved the problem.

Another way could be calculating the cell content height and defining them at heightForRowAt indexPath.

Swift - Dynamic UITableViewCell size based on image aspect ratio

For achieve this I use first a dictionary [Int:CGFloat] to keep the calculated heigths of cells then in the heightForRowAtIndexpath method use the values keeped in your dictionary, in your cellForRowAtIndexpath method you should download your image, calculate the aspect ratio, multiply your cell width or your image width by your aspect ratio and put the height calculated in correspondent IndexPath number in your dictionary

In code something like this, this is an example of code using alamofire to load the images

    var rowHeights:[Int:CGFloat] = [:] //declaration of Dictionary

    //My heightForRowAtIndexPath method
    func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
        if let height = self.rowHeights[indexPath.row]{
            return height
        }else{
            return defaultHeight
        }
    }

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {

if let cell = tableView.dequeueReusableCell(withIdentifier: "ImageCell") as? ImageCell
        {
        let urlImage = Foundation.URL(string: "http://imageurl")
        cell.articleImage.af_setImage(withURL: urlImage, placeholderImage: self.placeholderImage, filter: nil, imageTransition: .crossDissolve(0.3), completion: { (response) in

            if let image = response.result.value{
                DispatchQueue.main.async {

                    let aspectRatio = (image! as UIImage).size.height/(image! as UIImage).size.width
                    cell.articleImage.image = image
                    let imageHeight = self.view.frame.width*aspectRatio
                    tableView.beginUpdates()
                    self.rowHeights[indexPath.row] = imageHeight
                    tableView.endUpdates()

                }
            }
        })
        }

I hope this helps

Constraining UIImageView height to respect dynamic UILabel height in UITableViewCell

Try setting thumbnail vertical compression resistance lower than title vertical hugging priority. In code it'll look like this:

    thumbnail.setContentCompressionResistancePriority(.defaultLow, for: .vertical)
    titleLabel.setContentHuggingPriority(.required, for: .vertical)

Set height for UIImageView in UITableViewCell using height / width values

What you need to do is deactivate your height constraint each time the cell is reused. Also, you need to set the height constraint equal to a multiple of the contentImageView width constraint, not the cell's width constraint. So your code should look something like this:

final class ContentArticleImage: UITableViewCell {

    var heightConstraint: NSLayoutConstraint?

    var ratio: CGFloat? { // 1000 / 600 (width / height)
        didSet {
            guard let ratio = ratio else { return }
            heightConstraint?.isActive = false
            heightConstraint = contentImageView.heightAnchor.constraint(equalTo: contentImageView.widthAnchor, multiplier: 1 / ratio)
            heightConstraint?.isActive = true
            heightConstraint?.priority = .defaultHigh
        }
    }

    lazy var contentImageView: UIImageView = {
        let imageView = UIImageView()
        imageView.translatesAutoresizingMaskIntoConstraints = false
        imageView.backgroundColor = .darkGray
        imageView.contentMode = .scaleAspectFit
        return imageView
    }()

    override init(style: UITableViewCell.CellStyle, reuseIdentifier: String?) {
        super.init(style: style, reuseIdentifier: reuseIdentifier)
        configureUI()
    }

    required init?(coder: NSCoder) {
        super.init(coder: coder)
        configureUI()
    }
}

Note that I'm setting the priority to .defaultHight just to silence a layout warning in the console.

How to display image in table view cell with dynamic height?

You can prevent this log by making priority of the imageView's bottom constraint to 999 , as when cell loads it suggests a static height that conflicts with your constraints that always happens in dynamic tableViews

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