---
title: preferredMaximumSize
framework: appkit
role: symbol
role_heading: Instance Property
path: appkit/nsviewcontroller/preferredmaximumsize
---

# preferredMaximumSize

For a view controller that is part of an app extension, the largest allowable size for the app extension’s primary view, in screen units.

## Declaration

```swift
var preferredMaximumSize: NSSize { get }
```

## Discussion

Discussion An app extension should return the maximum dimensions that are potentially useful for its root view, based on the items the service has been sent.  By default, the value of this property is a large or infinite size.

## See Also

### Related Documentation

- [preferredContentSize](appkit/nsviewcontroller/preferredcontentsize.md)

### Configuring an App Extension View Controller

- [extensionContext](appkit/nsviewcontroller/extensioncontext.md)
- [preferredScreenOrigin](appkit/nsviewcontroller/preferredscreenorigin.md)
- [preferredMinimumSize](appkit/nsviewcontroller/preferredminimumsize.md)
- [viewWillTransition(to:)](appkit/nsviewcontroller/viewwilltransition(to:).md)
- [sourceItemView](appkit/nsviewcontroller/sourceitemview.md)