I'm creating a horizontal scroll view through the collection view. I used flowlayout for layout, and I set the scroll direction to horizontal. I found a bug in this situation. If the width of the item is different, line spacing is not applied, but item spacing is applied. Since it is a horizontal scroll, line spacing should be applied in the direction of the column, but item spacing is applied. Does anyone know anything about this? // // ViewController.swift // minimumLineSpacingTest // // Created by Hoonki chae on 2023/07/12. // import UIKit class TestCell: UICollectionViewCell { } class ViewController: UIViewController { let collectionView = UICollectionView(frame: .zero, collectionViewLayout: UICollectionViewFlowLayout()) override func viewDidLoad() { super.viewDidLoad() self.view.backgroundColor = .white self.collectionView.frame = .init(origin: .init(x: 0, y: 100), size: .init(width: self.view.frame.width, height: 50)) self.view.addSubview(self.collectionView) self.collectionView.backgroundColor = .systemGray.withAlphaComponent(0.2) self.collectionView.delegate = self self.collectionView.dataSource = self self.collectionView.register(TestCell.self, forCellWithReuseIdentifier: "Cell") (self.collectionView.collectionViewLayout as? UICollectionViewFlowLayout)?.scrollDirection = .horizontal } } extension ViewController: UICollectionViewDelegate, UICollectionViewDataSource, UICollectionViewDelegateFlowLayout { func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int { return 5 } func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell { let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "Cell", for: indexPath) cell.backgroundColor = .green.withAlphaComponent(0.3) return cell } func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize { return .init(width: indexPath.item > 2 ? 150 : 140, height: 50) } func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumLineSpacingForSectionAt section: Int) -> CGFloat { return 20 } func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumInteritemSpacingForSectionAt section: Int) -> CGFloat { return 4 } }```