Swift 如何修复NSFetchedResultsController controllerDidChangeContent中的内存泄漏

问题： 当我评测我的应用程序时，函数控制器IDChangeContent中出现内存泄漏。Instruments告诉我泄漏应该在

self.collectionView？行中。performbatchUpdate（

中的{[unowned self]）。但是既然我已经添加了unowned self，但没有成功，怎么会有内存周期呢。你有什么提示如何修复此泄漏

创意： 这可能是由类中声明的数组

private var blockOperations=[BlockOperation]（）

引起的吗？但不可能将数组设置为弱

extension CollectionViewController: NSFetchedResultsControllerDelegate {

func controllerWillChangeContent(_ controller: NSFetchedResultsController<NSFetchRequestResult>) {
    self.blockOperations = []
}

func controller(_ controller: NSFetchedResultsController<NSFetchRequestResult>, didChange anObject: Any,
                at indexPath: IndexPath?, for type: NSFetchedResultsChangeType, newIndexPath: IndexPath?) {
    var operation: BlockOperation
    switch type {
    case .insert:
        guard let newIndexPath = newIndexPath else { return }
        operation = BlockOperation { [unowned self] in
            self.collectionView?.insertItems(at: [newIndexPath])
        }
    case .delete:
        guard let indexPath = indexPath else { return }
        operation = BlockOperation { [unowned self] in
            self.collectionView?.deleteItems(at: [indexPath])
        }
    case .update:
        guard let newIndexPath = newIndexPath else { return }
        operation = BlockOperation { [unowned self] in
            self.collectionView?.reloadItems(at: [newIndexPath])
        }
    case .move:
        guard let indexPath = indexPath else { return }
        guard let newIndexPath = newIndexPath else { return }
        operation = BlockOperation { [unowned self] in
            self.collectionView?.deleteItems(at: [indexPath])
            self.collectionView?.insertItems(at: [newIndexPath])
        }
    }
    blockOperations.append(operation)
}

func controllerDidChangeContent(_ controller: NSFetchedResultsController<NSFetchRequestResult>) {
    // in the next line there is the leak shown in Instruments
    self.collectionView?.performBatchUpdates({ [unowned self] in
        for block in self.blockOperations {
            block.start() }
    }, completion: { [unowned self] _ in
        self.blockOperations.removeAll()
    })
    updateView()
}

扩展集合视图控制器：NSFetchedResultsControllerDelegate{
func controllerWillChangeContent（\ucontroller:NSFetchedResultsController）{
self.blockOperations=[]
}
func控制器（u控制器：NSFetchedResultsController，didChange对象：Any，
在indexPath:indexPath？处，对于类型：NSFetchedResultsChangeType，newIndexPath:indexPath？）{
var操作：BlockOperation
开关类型{
案例.插入：
guard let newindepath=newindepath else{return}
操作=块操作{[unowned self]在
self.collectionView？.insertItems（位于：[newIndexPath]）
}
案例.删除：
guard let indepath=indepath else{return}
操作=块操作{[unowned self]在
self.collectionView？.deleteItems（位于：[indexPath]）
}
案例。更新：
guard let newindepath=newindepath else{return}
操作=块操作{[unowned self]在
self.collectionView？.reloadItems（位于：[newIndexPath]）
}
案件.动议：
guard let indepath=indepath else{return}
guard let newindepath=newindepath else{return}
操作=块操作{[unowned self]在
self.collectionView？.deleteItems（位于：[indexPath]）
self.collectionView？.insertItems（位于：[newIndexPath]）
}
}
blockOperations.append（操作）
}
func controllerDidChangeContent（\控制器：NSFetchedResultsController）{
//下一行是仪表中显示的泄漏
self.collectionView？.performbatchUpdate（{[unowned self]在中）
用于自阻塞操作中的阻塞{
block.start（）}
}，完成：{[unowned self]\uuIn
self.blockOperations.removeAll（）
})
updateView（）
}

}