# PreviewActivityBuilder ``` @resultBuilder struct PreviewActivityBuilder where A : ActivityAttributes ``` ## Topics ### Previewing Live Activities [`static func buildArray([[A.ContentState]]) -> [A.ContentState]`](/documentation/WidgetKit/PreviewActivityBuilder/buildArray(_:)) [`static func buildExpression(A.ContentState) -> [A.ContentState]`](/documentation/WidgetKit/PreviewActivityBuilder/buildExpression(_:)) [`static func buildPartialBlock(accumulated: [A.ContentState], next: [A.ContentState]) -> [A.ContentState]`](/documentation/WidgetKit/PreviewActivityBuilder/buildPartialBlock(accumulated:next:)) [`static func buildPartialBlock(first: [A.ContentState]) -> [A.ContentState]`](/documentation/WidgetKit/PreviewActivityBuilder/buildPartialBlock(first:)) --- 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)