---
title: willPopUpNotification
framework: appkit
role: symbol
role_heading: Type Property
path: appkit/nscombobox/willpopupnotification
---

# willPopUpNotification

Posted whenever the pop-up list of the NSComboBox is going to be displayed.

## Declaration

```swift
class let willPopUpNotification: NSNotification.Name
```

## Discussion

Discussion The notification object is the NSComboBox whose pop-up window will be displayed. This notification does not contain a userInfo dictionary. To observe this notification using Swift concurrency, use NSComboBox.WillPopUpMessage.

## See Also

### Notifications

- [selectionDidChangeNotification](appkit/nscombobox/selectiondidchangenotification.md)
- [selectionIsChangingNotification](appkit/nscombobox/selectionischangingnotification.md)
- [willDismissNotification](appkit/nscombobox/willdismissnotification.md)