---
title: "transformPreference(_:_:)"
framework: swiftui
role: symbol
role_heading: Instance Method
path: "swiftui/view/transformpreference(_:_:)"
---

# transformPreference(_:_:)

Applies a transformation to a preference value.

## Declaration

```swift
nonisolated func transformPreference<K>(_ key: K.Type = K.self, _ callback: @escaping (inout K.Value) -> Void) -> some View where K : PreferenceKey

```

## See Also

### Setting preferences

- [preference(key:value:)](swiftui/view/preference(key:value:).md)