NgDocOverlayService

constructor(
	private overlay: Overlay, 
	private ngZone: NgZone, 
	private injector: Injector, 
	@Optional() private router?: Router | undefined
): NgDocOverlayService;

connectedPositionStrategy(origin: FlexibleConnectedPositionStrategyOrigin, positions: NgDocOverlayPosition | NgDocOverlayPosition[]): FlexibleConnectedPositionStrategy;

globalPositionStrategy(): GlobalPositionStrategy;

open(content: NgDocContent, config: NgDocOverlayConfig, providers: StaticProvider[] = []): NgDocOverlayRef<R>;

scrollStrategy(): ScrollStrategyOptions;