ViewportStatusObserver

@_spi(Experimental)
public protocol ViewportStatusObserver : AnyObject

ViewportStatusObserver must be implemented by objects that wish to register themselves using addStatusObserver(_:) so that they can observe status changes.

See also

addStatusObserver(_:) for an important note about how these notifications are delivered asynchronously.


                    
                    
                    viewportStatusDidChange(from:to:reason:)

Called whenever status changes.

Declaration

Swift

func viewportStatusDidChange(from fromStatus: ViewportStatus,
                             to toStatus: ViewportStatus,
                             reason: ViewportStatusChangeReason)

Parameters

`fromStatus`	The value of `status` prior to the change.
`toStatus`	The value of `status` after the change.
`reason`	A `ViewportStatusChangeReason` that indicates what initiated the change.