How to add subview to stackview in table view cell? - ios

Question

I am in need to add the label as subview to UIStackView in table view cell.
I have created label as
let nameLabel=UILabel()
nameLabel.text=names[indexPath.row]
Where name is an array which is a type of String
My code is
class ViewController: UIViewController,UITableViewDelegate,UITableViewDataSource
{
let names=["Amutha","Priya","Amuthapriya","Priyasri","Kavisha"]
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int
{
return names.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) ->
UITableViewCell
{
let cell=tableView.dequeueReusableCell(withIdentifier: "cell") as! ViewCell
for name in names
{
let nameLabel=UILabel()
nameLabel.text=name
cell.nameStackView!.addSubview(nameLabel)
}
return cell
}
}
Why I am getting a null pointer exception when I add a label to stackview?
Any help will be much appreciated.

Answer 1

Change
cell.nameStackView!.addSubview(nameLabel)
To
cell.nameStackView!.addArrangedSubview(nameLabel)

Answer 2

You can use below code to add UIStackView as per your need.
let titleLabel = UILabel()
let subtitleLabel = UILabel()
lazy var titleStackView: UIStackView = {
titleLabel.textAlignment = .center
titleLabel.text = "Good Morning"
titleLabel.textColor = UIColor.white
titleLabel.font = UIFont(name: "ProximaNova-Regular", size: 12.0)
subtitleLabel.textAlignment = .center
subtitleLabel.text = "--"
subtitleLabel.textColor = UIColor.white
subtitleLabel.heightAnchor.constraint(equalToConstant: 30.0).isActive = true
subtitleLabel.font = UIFont(name: "DublinSpurs", size: 20.0)
let stackView = UIStackView(arrangedSubviews: [subtitleLabel])
stackView.axis = .vertical/.horizontal
return stackView
}()
Also try replacing
for name in names
{
let nameLabel=UILabel()
nameLabel.text=name
cell.nameStackView!.addSubview(nameLabel)
}
with
let nameLabel=UILabel()
nameLabel.text = names[indexPath.row]
cell.nameStackView!.addSubview(nameLabel)

Answer 3

If you have nameStackView in storyboard or xib, make sure the IBOutlet is connected properly. If you have created the nameStackView programmatically make sure it is initialised.
And remove all existing labels from the stackview, else you'll have duplicate labels on each scroll
class ViewCell: UITableViewCell {
//Make sure IBOutlet is connected properly
#IBOutlet weak var nameStackView: UIStackView!
}
ViewController
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell
{
let cell = tableView.dequeueReusableCell(withIdentifier: "cell") as! ViewCell
for name in names
{
cell.nameStackView.arrangedSubviews.forEach { cell.nameStackView.removeArrangedSubview($0) }
let nameLabel=UILabel()
nameLabel.text=name
cell.nameStackView.addSubview(nameLabel)
}
return cell
}

Answer 4

Try below code
let nameLabel = UILabel()
cell.nameStackView.addArrangedSubview(nameLabel)

Answer 5

Try initializing the stackview and label in your ViewCell class.
class ViewCell: UITableViewCell {
let nameLabel: UILabel = {
let label = UILabel()
label.font = UIFont.systemFont(ofSize: 14)
return label
}()
let nameStackView: UIStackView = {
let stackView = UIStackView()
stackView.axis = .vertical
return stackView
}()
override init(style: UITableViewCell.CellStyle, reuseIdentifier: String?) {
super .init(style: style, reuseIdentifier: reuseIdentifier)
self.configureStackView()
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
func configureStackView()
{
addSubview(nameStackView)
nameStackView.translatesAutoresizingMaskIntoConstraints = false
nameStackView.topAnchor.constraint(equalTo: topAnchor).isActive = true
nameStackView.leadingAnchor.constraint(equalTo: leadingAnchor).isActive = true
nameStackView.trailingAnchor.constraint(equalTo: trailingAnchor).isActive = true
nameStackView.bottomAnchor.constraint(equalTo: bottomAnchor).isActive = true
nameStackView.addArrangedSubview(nameLabel)
nameLabel.translatesAutoresizingMaskIntoConstraints = false
nameLabel.topAnchor.constraint(equalTo: nameStackView.topAnchor,
constant:10).isActive = true
nameLabel.leadingAnchor.constraint(equalTo: nameStackView.leadingAnchor,
constant:10).isActive = true
nameLabel.trailingAnchor.constraint(equalTo: nameStackView.trailingAnchor,
constant:-10).isActive = true
nameLabel.bottomAnchor.constraint(equalTo: nameStackView.bottomAnchor,
constant:-10).isActive = true
}
}
This code is in case you didn't create your stackview in storyboard.
Now in your ViewController class, add the following code in your cellForRowAt method.
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) ->
UITableViewCell
{
let cell=tableView.dequeueReusableCell(withIdentifier: "cell") as! ViewCell
cell.nameLabel.text = names[indexPath.row]
return cell
}
Hope, this solution works for you.