Adds an identifiable action to the list of actions executed by the node.
- iOS 8.0+
- macOS 10.10+
- tvOS 9.0+
- watchOS 2.0+
The action to be performed.
A unique key used to identify the action.
This method is identical to
run, but the action is stored and identified so that you can retrieve or cancel it later. If an action using the same key is already running, SceneKit removes it before adding the new action.