# init(_:content:) Creates an instance that animates the property of the root value at the given key path. ``` init(_ keyPath: WritableKeyPath, @KeyframeTrackContentBuilder content: () -> Content) ``` ## Parameters `keyPath` The property to animate. `content` A keyframe collection builder closure containing the keyframes that control the interpolation curve. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)