arrays - 如何将 UITableViewCell 内的 UICollectionViewCell 的选定索引路径保存到数组？

Question

我在 UITableView 中有 UICollectionViewCells。我正在尝试为 UITableView 的每一行突出显示选定的 UICollectionViewCell。当 UITableView 重新加载时，选定的单元格应该突出显示。这是示例代码:

var selectedIndexes = [IndexPath]()
var familyAModelArray : [[Child1]] = []
var childAModelArray : [Child1] = []

func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {

        return familyAModelArray[collectionView.tag].count

}

func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {


        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "Cell", for: indexPath) as! ChildCollectionViewCell

        cell.nameLabel.text = childAModelArray[indexPath.row].person! // or childArray

        cell.profilePicture.sd_setImage(with: URL(string: "\(baseUrl)\(childAModelArray[indexPath.row].image!)"), placeholderImage: #imageLiteral(resourceName: "avatar.png"), options: [.continueInBackground,.progressiveDownload])

     return cell
        }

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

        selectedIndexes.append(indexPath)

        let i = selectedIndexes[collectionView.tag][indexPath.row]

}

这里我得到了超出范围的索引:let i = selectedIndexes[collectionView.tag][indexPath.row]

如何实现这一点？有什么想法吗？提前致谢。

Answer 1

检查单元格是否被选中的一个好方法是更改​​单元格的背景颜色

func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
    let cell = collectionView.cellForItemAt(indexPath)
    cell.backgroundColor = .red

    // append the selected red cells to an array like such
    selectedIndices.append(indexPath)


}

一旦 tableView 重新加载，您可以检查数组中的选定索引并更改背景颜色。

func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {


    let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "Cell", for: indexPath) as! ChildCollectionViewCell

    if selectedIndices.contains(indexPath) {
        cell.backgroundColor = .red
        // check if the index matches a selectedIndex and change it to the selected color.
    }
    cell.nameLabel.text = childAModelArray[indexPath.row].person! // or childArray

    cell.profilePicture.sd_setImage(with: URL(string: "\(baseUrl)\(childAModelArray[indexPath.row].image!)"), placeholderImage: #imageLiteral(resourceName: "avatar.png"), options: [.continueInBackground,.progressiveDownload])

 return cell
}

现在重新加载后，将再次调用 cellForItemAt 函数，所选索引路径中的索引将再次变为红色。