swift - 垂直和水平滚动collectionView选择单元格问题

Question

我有一个双向滚动的collectionView，我希望单元格backgroundView在选择时出现并在取消选择时消失。我声明了一个包含选定索引路径的数组，以在 cellForItemAt indexPath 函数中对其进行测试，但它不起作用。请提供任何帮助!这是我的代码:

    var selectedIndexPaths:[IndexPath]=[]

 func collectionView(_ collectionView: UICollectionView, didDeselectItemAt indexPath: IndexPath) {
    if(selectedIndexPaths.contains(indexPath)){
        selectedIndexPaths=selectedIndexPaths.filter { $0 != indexPath }
    } 
}
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
    selectedIndexPaths.append(indexPath)
 collectionView.reloadItems(at: [indexPath])
}

func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
    // swiftlint:disable force_cast
    let cell = collectionView.dequeueReusableCell(withReuseIdentifier: contentCellIdentifier,
                                               for: indexPath) as! UserCollectionCell

    if(selectedIndexPaths.contains(indexPath) ){
        cell.backgroundView?.isHidden=false
    }
    else{
        cell.backgroundView?.isHidden=true
    }

    return cell
}

Answer 1

删除

 func collectionView(_ collectionView: UICollectionView, didDeselectItemAt indexPath: IndexPath) {
    if(selectedIndexPaths.contains(indexPath)){
        selectedIndexPaths=selectedIndexPaths.filter { $0 != indexPath }
    } 
} 

当您选择一个单元格并自动取消选择之前选择的单元格时调用它，然后将其更改为

func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {

    if selectedIndexPaths.contains(indexPath) {
        selectedIndexPaths = selectedIndexPaths.filter { $0 != indexPath }
    }
    else {
       selectedIndexPaths.append(indexPath)
    }
    collectionView.reloadItems(at: [indexPath])
}