在Swift中更改tvOS中collectionView单元的zPosition

问题描述

我正在尝试通过设置zPosition来将聚焦的collectionView单元格置于最前面，如下面的代码所示。但这似乎没有任何效果。请让我知道正确的操作步骤。

 func collectionView(_ collectionView: UICollectionView,didUpdateFocusIn context: UICollectionViewFocusUpdateContext,with coordinator: UIFocusAnimationCoordinator) {
        if let prevIndexPath = context.prevIoUslyFocusedindexPath,let cell = collectionView.cellForItem(at: prevIndexPath) {
            cell.contentView.layer.zPosition = 0
        }
        
        if let indexPath = context.nextFocusedindexPath,let cell = collectionView.cellForItem(at: indexPath) {
            cell.contentView.layer.zPosition = 1.0
            collectionView.scrollToItem(at: indexPath,at: [.centeredHorizontally,.centeredVertically],animated: true)
        }
    }

解决方法

由于我正在尝试在collectionViewCell中显示图像，因此无需设置zPosition，我们可以更改AdjustsImageWhenAncestorFocused属性。我找到了相同的解决方案。

我必须如下设置imageview的adjustsImageWhenAncestorFocused属性：

func collectionView(_ collectionView: UICollectionView,didUpdateFocusIn context: UICollectionViewFocusUpdateContext,with coordinator: UIFocusAnimationCoordinator) {
        if let prevIndexPath = context.previouslyFocusedIndexPath,let cell = collectionView.cellForItem(at: prevIndexPath) {
                       cell.imageView.adjustsImageWhenAncestorFocused = false
        }
        
        if let indexPath = context.nextFocusedIndexPath,let cell = collectionView.cellForItem(at: indexPath) {
                       cell.imageView.adjustsImageWhenAncestorFocused = true
            collectionView.scrollToItem(at: indexPath,at: [.centeredHorizontally,.centeredVertically],animated: true)
        }
    }