license import { OverlayReference } from '../overlay-reference' ; /** Strategy for setting the position on an overlay. */ export interface PositionStrategy { /** Attaches this position strategy to an overlay. */ attach ( overlayRef ) : void ; /** Updates the position of the overlay element. */ apply ( ) : void ; /** Called when the overlay is detached. */ detach ? ( ) : void ; /** Cleans up any DOM modifications made by the position strategy, if necessary. */ dispose ( ) : void ; }