---
title: "applySnapshot(usingReloadData:completion:)"
framework: uikit
role: symbol
role_heading: Instance Method
path: "uikit/uicollectionviewdiffabledatasourcereference/applysnapshot(usingreloaddata:completion:)"
---

# applySnapshot(usingReloadData:completion:)

Resets the UI to reflect the state of the data in the snapshot without computing a diff or animating the changes, optionally executing a completion handler.

## Declaration

```swift
func applySnapshot(usingReloadData snapshot: NSDiffableDataSourceSnapshotReference, completion: (() -> Void)? = nil)
```

## Parameters

- `snapshot`: The snapshot that reflects the new state of the data in the collection view.
- `completion`: A closure to execute when the reload completes. This closure has no return value and takes no parameters. The system calls this closure from the main queue.

## Discussion

Discussion The system interrupts any ongoing item animations and immediately reloads the collection view’s content. You can safely call this method from a background queue, but you must do so consistently in your app. Always call this method exclusively from the main queue or from a background queue.

## See Also

### Updating data

- [snapshot()](uikit/uicollectionviewdiffabledatasourcereference/snapshot().md)
- [applySnapshot(_:animatingDifferences:)](uikit/uicollectionviewdiffabledatasourcereference/applysnapshot(_:animatingdifferences:).md)
- [applySnapshot(_:animatingDifferences:completion:)](uikit/uicollectionviewdiffabledatasourcereference/applysnapshot(_:animatingdifferences:completion:).md)
- [applySnapshot(usingReloadData:)](uikit/uicollectionviewdiffabledatasourcereference/applysnapshot(usingreloaddata:).md)