The Scene Systems Shutdown Event.
This event is dispatched by a Scene during the Scene Systems shutdown process.
Listen to it from a Scene using
You should free-up any resources that may be in use by your Scene in this event handler, on the understanding
that the Scene may, at any time, become active again. A shutdown Scene is not 'destroyed', it's simply not
currently active. Use the
DESTROY event to completely clear resources.
A reference to the Scene Systems class of the Scene that emitted this event.
An optional data object that was passed to this Scene when it was shutdown.