I am using two nested collection views. I have added the ChildCollectionView to the ParentCollectionViewCell, and ChildCollectionView have 3 cells in it but the ParentCollectionViewCell does not adjust the frame of the cell as per the content.
Here's the code,
ParentCollectionView
class ViewController: UIViewController {
var parentCollectionView: UICollectionView = {
let _collectionView = UICollectionView.init(frame: .zero, collectionViewLayout: UICollectionViewFlowLayout.init())
return _collectionView
}()
let id = "ParentCollectionViewCell"
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
view.addSubview(parentCollectionView)
parentCollectionView.translatesAutoresizingMaskIntoConstraints = false
NSLayoutConstraint.activate([
parentCollectionView.leadingAnchor.constraint(equalTo: view.leadingAnchor),
parentCollectionView.trailingAnchor.constraint(equalTo: view.trailingAnchor),
parentCollectionView.topAnchor.constraint(equalTo: view.topAnchor),
parentCollectionView.bottomAnchor.constraint(equalTo: view.bottomAnchor)
])
parentCollectionView.dataSource = self
parentCollectionView.register(UINib(nibName: id, bundle: nil), forCellWithReuseIdentifier: id)
if let flowLayout = parentCollectionView.collectionViewLayout as? UICollectionViewFlowLayout {
flowLayout.estimatedItemSize = UICollectionViewFlowLayout.automaticSize
}
}
}
extension ViewController: UICollectionViewDataSource {
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
1
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: id, for: indexPath) as! ParentCollectionViewCell
cell.backgroundColor = .red
return cell
}
}
ParentCollectionViewCell
class ParentCollectionViewCell: UICollectionViewCell {
var childCollectionView: UICollectionView = {
let _collectionView = UICollectionView.init(frame: .zero, collectionViewLayout: UICollectionViewFlowLayout.init())
return _collectionView
}()
let reuseId = "ChildCollectionViewCell"
private let data = ["ChildCell1","ChildCell2","ChildCell3"]
override func awakeFromNib() {
super.awakeFromNib()
// Initialization code
setupViews()
}
func setupViews() {
contentView.addSubview(childCollectionView)
childCollectionView.translatesAutoresizingMaskIntoConstraints = false
NSLayoutConstraint.activate([
childCollectionView.leadingAnchor.constraint(equalTo: contentView.leadingAnchor),
childCollectionView.trailingAnchor.constraint(equalTo: contentView.trailingAnchor),
childCollectionView.topAnchor.constraint(equalTo: contentView.topAnchor),
childCollectionView.bottomAnchor.constraint(equalTo: contentView.bottomAnchor),
childCollectionView.widthAnchor.constraint(equalToConstant: 360)
])
childCollectionView.dataSource = self
childCollectionView.register(UINib(nibName: reuseId, bundle: nil), forCellWithReuseIdentifier: reuseId)
if let flowLayout = childCollectionView.collectionViewLayout as? UICollectionViewFlowLayout {
flowLayout.estimatedItemSize = UICollectionViewFlowLayout.automaticSize
}
}
}
extension ParentCollectionViewCell: UICollectionViewDataSource {
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
data.count
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: reuseId, for: indexPath) as! ChildCollectionViewCell
cell.backgroundColor = .gray
cell.setupViews()
return cell
}
}
ChildCollectionViewCell
class ChildCollectionViewCell: UICollectionViewCell {
override func awakeFromNib() {
super.awakeFromNib()
// Initialization code
}
func setupViews() {
let label = UILabel()
label.text = "Child Collection"
label.numberOfLines = 0
label.font = label.font.withSize(50)
contentView.addSubview(label)
label.translatesAutoresizingMaskIntoConstraints = false
NSLayoutConstraint.activate([
label.leadingAnchor.constraint(equalTo: contentView.leadingAnchor),
label.trailingAnchor.constraint(equalTo: contentView.trailingAnchor),
label.topAnchor.constraint(equalTo: contentView.topAnchor),
label.bottomAnchor.constraint(equalTo: contentView.bottomAnchor)
])
}
}
Current Output Current Output
Expected Output Expected Output
