---
title: significantTimeChangeNotification
framework: uikit
role: symbol
role_heading: Type Property
path: uikit/uiapplication/significanttimechangenotification
---

# significantTimeChangeNotification

A notification that posts when there’s a significant change in time.

## Declaration

```swift
nonisolated class let significantTimeChangeNotification: NSNotification.Name
```

## Mentioned in

Processing queued notifications

## Discussion

Discussion The system posts this notification when, for example, there’s a change to a new day (midnight), a carrier time update, or a change to, or from, daylight savings time. The notification doesn’t contain a user info dictionary.

## See Also

### Responding to environment changes

- [applicationProtectedDataDidBecomeAvailable(_:)](uikit/uiapplicationdelegate/applicationprotecteddatadidbecomeavailable(_:).md)
- [applicationProtectedDataWillBecomeUnavailable(_:)](uikit/uiapplicationdelegate/applicationprotecteddatawillbecomeunavailable(_:).md)
- [applicationDidReceiveMemoryWarning(_:)](uikit/uiapplicationdelegate/applicationdidreceivememorywarning(_:).md)
- [applicationSignificantTimeChange(_:)](uikit/uiapplicationdelegate/applicationsignificanttimechange(_:).md)
- [protectedDataDidBecomeAvailableNotification](uikit/uiapplication/protecteddatadidbecomeavailablenotification.md)
- [protectedDataWillBecomeUnavailableNotification](uikit/uiapplication/protecteddatawillbecomeunavailablenotification.md)
- [didReceiveMemoryWarningNotification](uikit/uiapplication/didreceivememorywarningnotification.md)