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  "title" : "Alert Levels"
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# Alert Levels

Flags identifying the seriousness of a user notification.

## Discussion

If you specify an icon to display in the dialog, this icon overrides the default icon used for each alert level.

## Topics

### Constants

[`var kCFUserNotificationStopAlertLevel: CFOptionFlags`](/documentation/CoreFoundation/kCFUserNotificationStopAlertLevel)

The notification is very serious.

[`var kCFUserNotificationNoteAlertLevel: CFOptionFlags`](/documentation/CoreFoundation/kCFUserNotificationNoteAlertLevel)

The notification is not very serious.

[`var kCFUserNotificationCautionAlertLevel: CFOptionFlags`](/documentation/CoreFoundation/kCFUserNotificationCautionAlertLevel)

The notification is somewhat serious.

[`var kCFUserNotificationPlainAlertLevel: CFOptionFlags`](/documentation/CoreFoundation/kCFUserNotificationPlainAlertLevel)

The notification is not serious.


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