Assigns a publisher’s output to a property of an object.
SDKs
- iOS 13.0+
- macOS 10.15+
- Mac Catalyst 13.0+
- tvOS 13.0+
- watchOS 6.0+
- Xcode 11.0+
Framework
- Combine
Declaration
func assign<Root>(to keyPath: ReferenceParameters
keyPathA key path that indicates the property to assign. See Key-Path Expression in The Swift Programming Language to learn how to use key paths to specify a property of an object.
objectThe object that contains the property. The subscriber assigns the object’s property every time it receives a new value.
Return Value
An Any instance. Call cancel() on this instance when you no longer want the publisher to automatically assign the property. Deinitializing this instance will also cancel automatic assignment.
Discussion
Use the assign(to: subscriber when you want to set a given property each time a publisher produces a value.
For example, given a type My with the property date, the following code uses a Timer to set the date property once a second.
let cancellable = Timer.publish(every: 1, on: .main, in: .default)
.autoconnect()
.assign(to: \MyViewModel.date, on: viewModel)