---
title: "windowWillEnterFullScreen(_:)"
framework: appkit
role: symbol
role_heading: Instance Method
path: "appkit/nswindowdelegate/windowwillenterfullscreen(_:)"
---

# windowWillEnterFullScreen(_:)

The window is about to enter full-screen mode.

## Declaration

```swift
@MainActor optional func windowWillEnterFullScreen(_ notification: Notification)
```

## Parameters

- `notification`: A notification named doc://com.apple.appkit/documentation/AppKit/NSWindow/willEnterFullScreenNotification.

## See Also

### Managing Full-Screen Presentation

- [window(_:willUseFullScreenContentSize:)](appkit/nswindowdelegate/window(_:willusefullscreencontentsize:).md)
- [window(_:willUseFullScreenPresentationOptions:)](appkit/nswindowdelegate/window(_:willusefullscreenpresentationoptions:).md)
- [windowDidEnterFullScreen(_:)](appkit/nswindowdelegate/windowdidenterfullscreen(_:).md)
- [windowWillExitFullScreen(_:)](appkit/nswindowdelegate/windowwillexitfullscreen(_:).md)
- [windowDidExitFullScreen(_:)](appkit/nswindowdelegate/windowdidexitfullscreen(_:).md)