# AttributeContainer.Builder A type that iteratively builds attribute containers by setting attribute values. ``` struct Builder where T : AttributedStringKey ``` ## Overview The [`AttributeContainer.Builder`](/documentation/Foundation/AttributeContainer/Builder) type lets you build [`AttributeContainer`](/documentation/Foundation/AttributeContainer) instances by chaining together several attributes in one expression. The following example shows this approach: ```swift // An attribute container with the link and backgroundColor attributes. let myContainer = AttributeContainer().link(myURL).backgroundColor(.yellow) ``` The first part of this expression, `AttributeContainer().link(URL(myURL))`, creates a builder to apply the [`link`](/documentation/Foundation/AttributeScopes/FoundationAttributes/link) attribute to the empty [`AttributeContainer`](/documentation/Foundation/AttributeContainer). The builder’s [`callAsFunction(_:)`](/documentation/Foundation/AttributeContainer/Builder/callAsFunction(_:)) returns a new [`AttributeContainer`](/documentation/Foundation/AttributeContainer) with this attribute set. Then the `backgroundColor(.yellow)` creates a second builder to modify the just-returned [`AttributeContainer`](/documentation/Foundation/AttributeContainer) by adding the [`backgroundColor`](/documentation/Foundation/AttributeScopes/SwiftUIAttributes/backgroundColor) attribute. The result is an [`AttributeContainer`](/documentation/Foundation/AttributeContainer) with both attributes set. ## Topics ### Calling Builder Functions [`func callAsFunction(T.Value) -> AttributeContainer`](/documentation/Foundation/AttributeContainer/Builder/callAsFunction(_:)) Builds an attribute container by setting an attribute and returning a modified attribute container. ## Relationships ### Conforms To [`SendableMetatype`](/documentation/Swift/SendableMetatype) [`Sendable`](/documentation/Swift/Sendable) --- 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)