---
title: ALAssetsLibraryChangedNotification
framework: assetslibrary
role: symbol
role_heading: Global Variable
path: assetslibrary/alassetslibrarychangednotification
---

# ALAssetsLibraryChangedNotification

Sent when the contents of the assets library have changed from under the app that is using the data.

## Declaration

```occ
extern NSString * const ALAssetsLibraryChangedNotification;
```

## Discussion

Discussion In iOS 4.0, the notification’s object is nil. In iOS 4.1 and later, the notification object is the library object that posted the notification. In iOS 6.0 and later, the user information dictionary describes what changed: If the user information dictionary is nil, reload all assets and asset groups. If the user information dictionary an empty dictionary, there is no need to reload assets and asset groups. If the user information dictionary is not empty, reload the effected assets and asset groups. For the keys used, see Notification Keys. This notification is sent on an arbitrary thread.