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我似乎遇到了组合布局的内存泄漏，我的组大小导致我的标题和单元格的内存使用率极高。只是为了更详细地解释我正在尝试布局一个水平网格，其中项目具有基于屏幕宽度的 1:1 比例。

在我的情况下，我想要每行 5 个项目，它们是屏幕大小的 20%，每个项目之间有 1px 间距。并且应该估计标题的高度，以便它们根据内容自行调整大小。所以下面是我到目前为止的一个片段。

// MARK: Sizing Constants
private let itemRatio: CGFloat = 0.2

var layout: UICollectionViewCompositionalLayout {
    
    UICollectionViewCompositionalLayout { [weak self] (sectionIndex, _) -> NSCollectionLayoutSection? in
        
        guard let self = self else { return nil }
                    
        let item = NSCollectionLayoutItem(layoutSize: .init(widthDimension: .fractionalWidth(self.itemRatio),
                                                            heightDimension: .fractionalWidth(self.itemRatio)))
        item.contentInsets.trailing = 1
        item.contentInsets.bottom = 1

        let group = NSCollectionLayoutGroup.horizontal(layoutSize: .init(widthDimension: .fractionalWidth(1),
                                                                         heightDimension: .fractionalWidth(self.itemRatio)),
                                                       subitems: [item])
        let section = NSCollectionLayoutSection(group: group)
        
        // Enable this when finish working on the cells
        section.boundarySupplementaryItems = [
            .init(layoutSize: .init(widthDimension: .fractionalWidth(1),
                                    heightDimension: .estimated(38)), // Investigate why this is causing a memory leak...
                  elementKind: "CollectionViewHeader",
                  alignment: .topLeading)
        ]

        return section
    }
}

如果我将上面的以下代码更改为下面的代码，其中我为节标题定义了一个绝对值，那么一切都会正常呈现并且没有问题。

    // MARK: Sizing Constants
    private let itemRatio: CGFloat = 0.2
    
    var layout: UICollectionViewCompositionalLayout {
        
        UICollectionViewCompositionalLayout { [weak self] (sectionIndex, _) -> NSCollectionLayoutSection? in
            
            guard let self = self else { return nil }
                        
            let item = NSCollectionLayoutItem(layoutSize: .init(widthDimension: .fractionalWidth(self.itemRatio),
                                                                heightDimension: .fractionalWidth(self.itemRatio)))
            item.contentInsets.trailing = 1
            item.contentInsets.bottom = 1

            let group = NSCollectionLayoutGroup.horizontal(layoutSize: .init(widthDimension: .fractionalWidth(1),
                                                                             heightDimension: .fractionalWidth(self.itemRatio)),
                                                           subitems: [item])
            let section = NSCollectionLayoutSection(group: group)
            
            // Enable this when finish working on the cells
            section.boundarySupplementaryItems = [
                .init(layoutSize: .init(widthDimension: .fractionalWidth(1),
//                                        heightDimension: .estimated(38)), // Investigate why this is causing a memory leak...
                                        heightDimension: .absolute(sectionIndex < 1 ? 120 : 72)), // Investigate why this is causing a memory leak...
                      elementKind: "CollectionViewHeader",
                      alignment: .topLeading)
            ]

            return section
        }
    }

任何想法为什么会这样？

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