Subject

@propertyWrapper
public class Subject<Element> : Subscribable, Observer, ObservableConvertible

A subscribable source that can emit events to its observers and be an observer itself.

You can use it as a property wrapper to make the emission private in the class where it’s contained, but still expose an Observable to the other classes.

  • Creates a new subject.

    Declaration

    Swift

    public init()

  • The wrapped observable value for property wrapper usage.

    Declaration

    Swift

    public var wrappedValue: Observable<Element> { get }

  • Emits an element to all subscribers.

    Declaration

    Swift

    public func onNext(_ element: Element)

    Parameters

    element

    The element to emit.

  • Completes this subject, calling onComplete on all current subscribers. After completion, new subscribers immediately receive onComplete.

    Declaration

    Swift

    public func onComplete()

  • Declaration

    Swift

    public func asObservable() -> Observable<Element>

  • Declaration

    Swift

    public func subscribe<O>(_ observer: O) -> any Disposable where Element == O.Element, O : Observer

  • Subscribes the observer only once and then automatically disposes it.

    This is meant to be used when you only need one observer to be registered once. Use the standalone first() operator if multiple observers all need to register for one event.

    Declaration

    Swift

    @discardableResult
func subscribeOnce(_ observer: @escaping (Element) -> Void) -> any Disposable

    Return Value

    a Disposable that can be used to dispose this observer before the first event is sent to the observer, in case it’s not needed any longer.

Available where Element == Void

  • Emits a Void event to all subscribers.

    Declaration

    Swift

    func onNext()