无法转换类型“（_）-> Void？”的值到预期的参数类型'（（） - > Void）？

Question

无法转换 '(_) -> Void?' 类型的值到预期的参数类型'(() -> Void)？'

[![在此处输入图片描述][1]][1]

[1]:https://i.stack.imgur.com/M1MYV.png`func deselectSelectedCells() { 如果让开始 = startDateIndexPath { var section = start.section var item = start.item + 1

        if let cell = collectionView?.cellForItem(at: start) as? AirbnbDatePickerCell {
            cell.type.remove([.InBetweenDate, .SelectedStartDate, .SelectedEndDate, .Selected])
            cell.configureCell()
            collectionView?.deselectItem(at: start, animated: false)
        }

        if let end = endDateIndexPath {
            var indexPathArr = [IndexPath]()
            while section < months.count, section <= end.section {
                let curIndexPath = IndexPath(item: item, section: section)
                if let cell = collectionView?.cellForItem(at: curIndexPath) as? AirbnbDatePickerCell {
                    cell.type.remove([.InBetweenDate, .SelectedStartDate, .SelectedEndDate, .Selected])
                    cell.configureCell()
                    collectionView?.deselectItem(at: curIndexPath, animated: false)
                }

                if section == end.section && item >= end.item {
                    // stop iterating beyond end date
                    break
                } else if item >= (collectionView!.numberOfItems(inSection: section) - 1) {
                    // more than num of days in the month
                    section += 1
                    item = 0
                } else {
                    item += 1
                }
            }

            collectionView?.performBatchUpdates({
                (s) in
                self.collectionView?.reloadItems(at: indexPathArr)
            }, completion: nil)
        }
    }
}`

Answer 1

错误告诉您解决方案。 performBatchUpdates 接受不带参数的回调，但你在那里定义了一个参数。

删除performBatchUpdates（第40行）下声明回调参数的(s) in行。