问：

如果滚动到 collectionView，则特定单元格将隐藏在可见单元格中 我希望那个单元格不要隐藏

我不知道为什么会这样。

macOS 索诺玛 14.0 Xcode代码15.0.1 iOS的17.0.1

视频捕获 在此处输入图像描述

这是我的代码

extension ViewController: UICollectionViewDelegate, UICollectionViewDataSource, UICollectionViewDelegateFlowLayout {
    
    func setupCollectionView() {
        self.collectionView.delegate = self
        self.collectionView.dataSource = self
        
        self.collectionView.register(UINib(nibName: "CollectionViewCell", bundle: nil), forCellWithReuseIdentifier: "CollectionViewCell")
    }
    
    func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
        self.colors.count
    }
    
    func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
        let width = collectionView.frame.width - 40        
        let height = 100.0

        return CGSize(width: width, height: height)
    }
    
    func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumLineSpacingForSectionAt section: Int) -> CGFloat {
        let height = 100.0
        return -height * 0.6
    }
    
    func collectionView(_ collectionView: UICollectionView, didEndDisplaying cell: UICollectionViewCell, forItemAt indexPath: IndexPath) {
        guard let first = collectionView.indexPathsForVisibleItems.sorted(by: {
                  ($0.section, $0.item) < ($1.section, $1.item)
              }).first,
              let last = collectionView.indexPathsForVisibleItems.sorted(by: {
                  ($0.section, $0.item) < ($1.section, $1.item)
              }).last else { return }
        
        print("\(first) < \(indexPath) < \(last)")
    }
    
    func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "CollectionViewCell", for: indexPath) as! CollectionViewCell
        
        cell.contentsView.backgroundColor = self.colors[indexPath.item]
        cell.layer.zPosition = CGFloat(indexPath.section) * 1000.0 +  CGFloat(indexPath.row)
        
        return cell
    }
}

结果 打印 在此处输入图像描述

要 不隐藏，可见

尝试 1

    func collectionView(_ collectionView: UICollectionView, didEndDisplaying cell: UICollectionViewCell, forItemAt indexPath: IndexPath) {
        guard let first = collectionView.indexPathsForVisibleItems.sorted(by: {
                  ($0.section, $0.item) < ($1.section, $1.item)
              }).first,
              let last = collectionView.indexPathsForVisibleItems.sorted(by: {
                  ($0.section, $0.item) < ($1.section, $1.item)
              }).last else { return }

        
        if first.section <= indexPath.section && last.section >= indexPath.section,
           first.item <= indexPath.item && last.item >= indexPath.item {
            
            cell.isHidden = false
        }
    }

结果

• 什么都不会发生

尝试 2

    func collectionView(_ collectionView: UICollectionView, didEndDisplaying cell: UICollectionViewCell, forItemAt indexPath: IndexPath) {
        guard let first = collectionView.indexPathsForVisibleItems.sorted(by: { ($0.section, $0.item) < ($1.section, $1.item)}).first,
              let last = collectionView.indexPathsForVisibleItems.sorted(by: { ($0.section, $0.item) < ($1.section, $1.item)}).last else { return }
                
        if first.section <= indexPath.section && last.section >= indexPath.section,
           first.item <= indexPath.item && last.item >= indexPath.item {

            self.collectionView.reloadItems(at: [indexPath])
        }
    }

结果

• 重复隐藏和显示