NotificationCenterObserving

public protocol NotificationCenterObserving

This helper protocol is introduced to make testing with NotificationCenter easier.

  • Adds an entry to the notification center’s dispatch table that includes a notification queue and a block to add to the queue, and an optional notification name and sender.

    Declaration

    Swift

    func addObserver(forName name: NSNotification.Name?, object obj: Any?, queue: OperationQueue?, using block: @escaping (Notification) -> Void) -> NSObjectProtocol

    Parameters

    name

    The name of the notification for which to register the observer; that is, only notifications with this name are used to add the block to the operation queue.
    obj

    The object whose notifications the observer wants to receive; that is, only notifications sent by this sender are delivered to the observer.
    queue

    The operation queue to which block should be added.
    block

    The block to be executed when the notification is received.

    Return Value

    An opaque object to act as the observer.

  • Removes all entries specifying a given observer from the notification center’s dispatch table.

    Declaration

    Swift

    func removeObserver(_ observer: Any)

    Parameters

    observer

    The observer to remove.