---
title: PHChange
framework: photos
role: symbol
role_heading: Class
path: photos/phchange
---

# PHChange

A description of a change that occurred in the photo library.

## Declaration

```swift
class PHChange
```

## Mentioned in

Observing Changes in the Photo Library

## Overview

Overview Photos provides PHChange objects to notify your app of changes to the assets and collections managed by the Photos app. To receive change information, adopt the PHPhotoLibraryChangeObserver protocol and register your observer with the shared PHPhotoLibrary object. After Photos provides a change object, you use its methods to get a change details object. Call the changeDetailsForObject: or changeDetails(for:) method, passing an asset or collection object you’ve previously fetched or a fetch result containing several such objects. The resulting PHObjectChangeDetails or PHFetchResultChangeDetails object describes any changes that have happened to the object or fetch result since you last fetched it.

## Topics

### Getting Change Details

- [changeDetails(for:)](photos/phchange/changedetails(for:)-33a6n.md)
- [changeDetails(for:)](photos/phchange/changedetails(for:)-536rd.md)
- [changeDetails(for:)](photos/phchange/changedetails(for:)-2fne7.md)

## Relationships

### Inherits From

- [NSObject](objectivec/nsobject-swift.class.md)

### Conforms To

- [CVarArg](swift/cvararg.md)
- [CustomDebugStringConvertible](swift/customdebugstringconvertible.md)
- [CustomStringConvertible](swift/customstringconvertible.md)
- [Equatable](swift/equatable.md)
- [Hashable](swift/hashable.md)
- [NSObjectProtocol](objectivec/nsobjectprotocol.md)
- [Sendable](swift/sendable.md)
- [SendableMetatype](swift/sendablemetatype.md)

## See Also

### Observing Library Changes

- [Observing Changes in the Photo Library](photokit/observing-changes-in-the-photo-library.md)
- [register(_:)](photos/phphotolibrary/register(_:)-6y3b9.md)
- [unregisterChangeObserver(_:)](photos/phphotolibrary/unregisterchangeobserver(_:).md)
- [PHPhotoLibraryChangeObserver](photos/phphotolibrarychangeobserver.md)
- [PHObjectChangeDetails](photos/phobjectchangedetails.md)
- [PHFetchResultChangeDetails](photos/phfetchresultchangedetails.md)