new ()
read onlycomplete:Bool
onComplete:_Event_Void_Void<Void ‑> Void>
onProgress:_Event_Int_Int_Void<Int ‑> Int ‑> Void>
addLibrary (library:AssetLibrary):Void
addLibraryName (name:String):Void
create (config:Config):Void
load ():Void