case activeThe scene is in the foreground and interactive.
case inactiveThe scene is in the foreground but should pause its work.
Discussion 議論
Do as little as possible in a scene that’s in the background phase. The background phase can precede termination, so do any cleanup work immediately upon entering this state. For example, close any open files and network connections. However, a scene can also return to the Scene phase from the background.
Expect an app that enters the background phase to terminate.