# mask(_:) Masks this view using the alpha channel of the given view. ``` nonisolated func mask(_ mask: Mask) -> some View where Mask : View ``` ## Parameters `mask` The view whose alpha the rendering system applies to the specified view. ## Discussion Use `mask(_:)` when you want to apply the alpha (opacity) value of another view to the current view. This example shows an image masked by rectangle with a 10% opacity: ``` Image(systemName: "envelope.badge.fill") .foregroundColor(Color.blue) .font(.system(size: 128, weight: .regular)) .mask(Rectangle().opacity(0.1)) ```  --- 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)