NotificationCenter

public extension NotificationCenter




observeOnce(forName:object:queue:using:)

SwifterSwift: Adds a one-time 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 observeOnce(forName name: NSNotification.Name?,
                 object obj: Any? = nil,
                 queue: OperationQueue? = nil,
                 using block: @escaping (_ notification: Notification) -> Void)

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.
`notification`	The notification.