CFRunLoopObserverIsValid(_:)
Returns a Boolean value that indicates whether a CFRunLoopObserver object is valid and able to fire.
Declaration
func CFRunLoopObserverIsValid(_ observer: CFRunLoopObserver!) -> BoolParameters
- observer:
The run loop observer to examine.
Return Value
true if observer is valid, otherwise false.
Discussion
A nonrepeating observer is automatically invalidated after it is called once.