ios – 在uicollectionview中插入一个单元格的swift给了我一个错误

func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int
{
    return comments.count
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        let cell = commentSection.dequeueReusableCell(withReuseIdentifier: cellId, for: indexPath) as! CommentCell
        return cell
}

我有以下功能插入单元格

DispatchQueue.main.async{
                    let indexPath = IndexPath(row: self.comments.count, section: 0)
                    self.commentSection.insertItems(at: [indexPath])
                    self.commentSection.reloadData()
 }

但每当我运行此代码时,它会打印此错误

libc++abi.dylib: terminating with uncaught exception of type NSException

并将我重定向到AppDelegate文件.即使错误写得非常清楚我也无法理解问题

self.collectionView?.performBatchUpdates({
    let indexPath = IndexPath(row: self.comments.count, section: 0)
    comments.append(your_object) //add your object to data source first
    self.collectionView?.insertItems(at: [indexPath])
}, completion: nil)