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# AVAssetTrackTrackAssociationsDidChange

A notification the system posts when the track associations for an asset track change.

```
static let AVAssetTrackTrackAssociationsDidChange: NSNotification.Name
```

## Discussion

The system posts this notification only for changes that occur after an asset’s track’s <doc://com.apple.documentation/documentation/AVFoundation/AVAssetTrack/availableTrackAssociationTypes> property reaches a <doc://com.apple.documentation/documentation/AVFoundation/AVKeyValueStatus/loaded> status.

---

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