我正在尝试从map中删除叠加层。funcremoveMapOverlay(){varremoveOverlays:[AnyObject]!=self.mapView.overlays//Abovelinethrowsruntimeexceptionself.mapView.removeOverlays(removeOverlays)}self.mapView.overlays是AnyObject数组的类型。var覆盖:[AnyObject]!{获取}。所以最初我写varremoveOverlays=self.mapView.overlays它在运行时的这一行抛出EXC_BAD_INST