Observer

public final class Observer

An Observer is a simple wrapper around a function which can receive Events (typically from a Signal).

  • An initializer that accepts a closure accepting an event for the observer.

    Declaration

    Swift

    public init(_ action: @escaping Action)

    Parameters

    action

    A closure to lift over received event.

  • An initializer that accepts closures for different event types.

    Declaration

    Swift

    public convenience init(
	value: ((Value) -> Void)? = nil,
	failed: ((Error) -> Void)? = nil,
	completed: (() -> Void)? = nil,
	interrupted: (() -> Void)? = nil
)

    Parameters

    value

    Optional closure executed when a value event is observed.
    failed

    Optional closure that accepts an Error parameter when a failed event is observed.
    completed

    Optional closure executed when a completed event is observed.
    interruped

    Optional closure executed when an interrupted event is observed.

  • Puts an event into self.

    Declaration

    Swift

    public func send(_ event: Event)

  • Puts a value event into self.

    Declaration

    Swift

    public func send(value: Value)

    Parameters

    value

    A value sent with the value event.

  • Puts a failed event into self.

    Declaration

    Swift

    public func send(error: Error)

    Parameters

    error

    An error object sent with failed event.

  • Puts a completed event into self.

    Declaration

    Swift

    public func sendCompleted()

  • Puts an interrupted event into self.

    Declaration

    Swift

    public func sendInterrupted()

  • Binds a source to a target, updating the target’s value to the latest value sent by the source.

    Note

    Only value events will be forwarded to the Observer. The binding will automatically terminate when the target is deinitialized, or when the source sends a completed event.

    Declaration

    Swift

    @discardableResult
public static func <~
	<Source: BindingSource>
	(observer: Signal<Value, Error>.Observer, source: Source) -> Disposable?
	where Source.Value == Value

    Parameters

    target

    A target to be bond to.
    source

    A source to bind.

    Return Value

    A disposable that can be used to terminate binding before the deinitialization of the target or the source’s completed event.