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# NSUserNotificationCenterDelegate

An interface that enables customizing the behavior of the default notification center.

```
protocol NSUserNotificationCenterDelegate : NSObjectProtocol
```

## Topics

### User Notification Delivery Information

[`userNotificationCenter(_:didDeliver:)`](/documentation/Foundation/NSUserNotificationCenterDelegate/userNotificationCenter(_:didDeliver:))

Sent to the delegate when a notification delivery date has arrived.

[`userNotificationCenter(_:didActivate:)`](/documentation/Foundation/NSUserNotificationCenterDelegate/userNotificationCenter(_:didActivate:))

Sent to the delegate when a user clicks on a user notification presented by the user notification center.

### User Notification Display Override

[`userNotificationCenter(_:shouldPresent:)`](/documentation/Foundation/NSUserNotificationCenterDelegate/userNotificationCenter(_:shouldPresent:))

Sent to the delegate when the user notification center has decided not to present your notification.


---

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