ArgumentError: Error #2025: 提供的 DisplayObject 必须是调用者的子级。 at flash.display::DisplayObjectContainer/getChildIndex() at mx.managers::SystemManager/getChildIndex()[C:/autobuild/3.2.0/frameworks/projects/framework/src/mx/managers/SystemManager.as:1652] at mx.managers::SystemManager/mouseDownHandler()[C:/autobuild/3.2.0/frameworks/projects/framework/src/mx/managers/SystemManager.as:3439]