---
title: NSPopUpButton.WillPopUpMessage
framework: appkit
role: symbol
role_heading: Structure
path: appkit/nspopupbutton/willpopupmessage
---

# NSPopUpButton.WillPopUpMessage

## Declaration

```swift
struct WillPopUpMessage
```

## Topics

### Initializers

- [init(popUpButton:)](appkit/nspopupbutton/willpopupmessage/init(popupbutton:).md)

### Instance Properties

- [popUpButton](appkit/nspopupbutton/willpopupmessage/popupbutton.md)

## Relationships

### Conforms To

- [NotificationCenter.MainActorMessage](foundation/notificationcenter/mainactormessage.md)
- [SendableMetatype](swift/sendablemetatype.md)