# Binding A property wrapper type that can read and write a value owned by a source of truth. ``` @frozen @propertyWrapper @dynamicMemberLookup struct Binding ``` ## Overview Use a binding to create a two-way connection between a property that stores data, and a view that displays and changes the data. A binding connects a property to a source of truth stored elsewhere, instead of storing data directly. For example, a button that toggles between play and pause can create a binding to a property of its parent view using the `Binding` property wrapper. ``` struct PlayButton: View { @Binding var isPlaying: Bool var body: some View { Button(isPlaying ? "Pause" : "Play") { isPlaying.toggle() } } } ``` The parent view declares a property to hold the playing state, using the [`State`](/documentation/SwiftUI/State) property wrapper to indicate that this property is the value’s source of truth. ``` struct PlayerView: View { var episode: Episode @State private var isPlaying: Bool = false var body: some View { VStack { Text(episode.title) .foregroundStyle(isPlaying ? .primary : .secondary) PlayButton(isPlaying: $isPlaying) // Pass a binding. } } } ``` When `PlayerView` initializes `PlayButton`, it passes a binding of its state property into the button’s binding property. Applying the `$` prefix to a property wrapped value returns its [`projectedValue`](/documentation/SwiftUI/State/projectedValue), which for a state property wrapper returns a binding to the value. Whenever the user taps the `PlayButton`, the `PlayerView` updates its `isPlaying` state. A binding conforms to `Sendable` only if its wrapped value type also conforms to `Sendable`. It is always safe to pass a sendable binding between different concurrency domains. However, reading from or writing to a binding’s wrapped value from a different concurrency domain may or may not be safe, depending on how the binding was created. SwiftUI will issue a warning at runtime if it detects a binding being used in a way that may compromise data safety. > Note: To create bindings to properties of a type that conforms to the > > protocol, use the ``doc://com.apple.SwiftUI/documentation/SwiftUI/Bindable`` property wrapper. For more information, > see . ## Topics ### Creating a binding [`init ( _ :)`](/documentation/SwiftUI/Binding/init(_:)) Creates a binding by projecting the base value to a hashable value. [`init(projectedValue:)`](/documentation/SwiftUI/Binding/init(projectedValue:)) Creates a binding from the value of another binding. [`init ( get : set :)`](/documentation/SwiftUI/Binding/init(get:set:)) Creates a binding with closures that read and write the binding value. [`constant(_:)`](/documentation/SwiftUI/Binding/constant(_:)) Creates a binding with an immutable value. ### Getting the value [`wrappedValue`](/documentation/SwiftUI/Binding/wrappedValue) The underlying value referenced by the binding variable. [`projectedValue`](/documentation/SwiftUI/Binding/projectedValue) A projection of the binding value that returns a binding. [`subscript(dynamicMember:)`](/documentation/SwiftUI/Binding/subscript(dynamicMember:)) Returns a binding to the resulting value of a given key path. ### Managing changes [`id`](/documentation/SwiftUI/Binding/id) The stable identity of the entity associated with this instance, corresponding to the `id` of the binding’s wrapped value. [`animation(_:)`](/documentation/SwiftUI/Binding/animation(_:)) Specifies an animation to perform when the binding value changes. [`transaction(_:)`](/documentation/SwiftUI/Binding/transaction(_:)) Specifies a transaction for the binding. [`transaction`](/documentation/SwiftUI/Binding/transaction) The binding’s transaction. ## Relationships ### Conforms To [`DynamicProperty`](/documentation/SwiftUI/DynamicProperty) [`Copyable`](/documentation/Swift/Copyable) [`SendableMetatype`](/documentation/Swift/SendableMetatype) [`RandomAccessCollection`](/documentation/Swift/RandomAccessCollection) [`BidirectionalCollection`](/documentation/Swift/BidirectionalCollection) [`Sequence`](/documentation/Swift/Sequence) [`Escapable`](/documentation/Swift/Escapable) [`Collection`](/documentation/Swift/Collection) [`Sendable`](/documentation/Swift/Sendable) [`Identifiable`](/documentation/Swift/Identifiable) --- 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)