---
title: NSCollectionView.DropOperation
framework: appkit
role: symbol
role_heading: Enumeration
path: appkit/nscollectionview/dropoperation
---

# NSCollectionView.DropOperation

These constants specify if acceptance of a drop should be at the item it is dropped on or before the item. These constants are used by the  collectionView(_:acceptDrop:index:dropOperation:) and collectionView(_:validateDrop:proposedIndex:dropOperation:) methods in NSCollectionViewDelegate

## Declaration

```swift
enum DropOperation
```

## Topics

### Constants

- [NSCollectionView.DropOperation.on](appkit/nscollectionview/dropoperation/on.md)
- [NSCollectionView.DropOperation.before](appkit/nscollectionview/dropoperation/before.md)

### Initializers

- [init(rawValue:)](appkit/nscollectionview/dropoperation/init(rawvalue:).md)

## Relationships

### Conforms To

- [BitwiseCopyable](swift/bitwisecopyable.md)
- [Equatable](swift/equatable.md)
- [Hashable](swift/hashable.md)
- [RawRepresentable](swift/rawrepresentable.md)
- [Sendable](swift/sendable.md)
- [SendableMetatype](swift/sendablemetatype.md)

## See Also

### Constants

- [NSCollectionView.ScrollPosition](appkit/nscollectionview/scrollposition.md)