self sizing cell with uitableviewdiffabledatasource

Question

I have a detail ViewController whoose cells are defined by a custom uitableviewdiffabledata like this:

{ (_, indexPath, item) -> UITableViewCell? in
            let color = UIColor(named: "blue")!
            if let _ = item as? TextFieldItem, let cell = tableView.dequeueReusableCell(withIdentifier: "textField", for: indexPath) as? TextFieldTableViewCell {
                cell.textField.text = recipe.wrappedValue.name
                cell.textField.placeholder = NSLocalizedString("name", comment: "")
                cell.selectionStyle = .none
                cell.textChanged = nameChanged
                cell.backgroundColor = color
                return cell
            } else if let imageItem = item as? ImageItem, let imageCell = tableView.dequeueReusableCell(withIdentifier: "image", for: indexPath) as? ImageTableViewCell {
                imageCell.setup(imageData: imageItem.imageData)
                return imageCell
            } else if let _ = item as? AmountItem, let amountCell = tableView.dequeueReusableCell(withIdentifier: "times", for: indexPath) as? AmountTableViewCell{
                amountCell.setUp(with: recipe.wrappedValue.timesText, format: formatAmount)
                amountCell.backgroundColor = color
                return amountCell
            } else if item is InfoItem {
                return  InfoTableViewCell(infoText: Binding(get: {
                    return recipe.wrappedValue.info
                }, set: updateInfo), reuseIdentifier: "info")
            } else if let stripItem = item as? InfoStripItem, let infoStripCell = tableView.dequeueReusableCell(withIdentifier: "infoStrip", for: indexPath) as? InfoStripTableViewCell {
                infoStripCell.setUpCell(for: stripItem)
                return infoStripCell
            } else if let stepItem = item as? StepItem {
                let stepCell = StepTableViewCell(style: .default, reuseIdentifier: "step")
                stepCell.setUpCell(for: stepItem.step)
                return stepCell
            } else if let detailItem = item as? DetailItem, let cell = tableView.dequeueReusableCell(withIdentifier: "detail", for: indexPath) as? DetailTableViewCell {
                let title = NSAttributedString(string: detailItem.text, attributes: [.foregroundColor : UIColor.label])
                cell.textLabel?.attributedText = title
                cell.accessoryType = .disclosureIndicator
                cell.backgroundColor = color
                return cell
            }
            return UITableViewCell()
        }

and i want to make the InfoTableViewCell which is defined like this:

class InfoTableViewCell: UITableViewCell {
    @Binding private var infoText: String
    
    private var textView = UITextView()

    init(infoText: Binding<String>, reuseIdentifier: String?) {
        self._infoText = infoText
        super.init(style: .default, reuseIdentifier: reuseIdentifier)
        setup()
    }
    
    required init?(coder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
    
    private func setup() {
        self.addSubview(textView)
        textView.fillSuperview()
        
        
        textView.text = infoText
        textView.delegate = self
        
        textView.backgroundColor = UIColor(named: "blue")!
        textView.font = UIFont.preferredFont(forTextStyle: .body)
    }
    
}

extension InfoTableViewCell: UITextViewDelegate {
    
    func textViewDidChange(_ textView: UITextView) {
        self.infoText = textView.text
    }
    
}

and i want to make this cell to resize based on the text thats in the textField. Any tips on how to do that ? P. S. I am using the LBTA tools for filling the contents of the cell with the textField.

score -1 · Answer 1 · answered Aug 16 '20 at 17:39

In my experience, just omit the tableView(_:heightForRowAt:) tableview delegate. Then when creating your cells, create constraints that bind the top and bottom of your cell to the top and bottom of your content. The cell will then grow or shrink to meet the constraints.

In the init of your custom table view cell class:

textView.topAnchor.constraint(equalTo: self.topAnchor, constant: 8).isActive = true
textView.bottomAnchor.constraint(equalTo: self.bottomAnchor, constant: -8).isActive = true

Not sure how the LBTA tools will affect the behavior of this, so this might only work with vanilla UIKit.

self sizing cell with uitableviewdiffabledatasource

1 Answers1