import { Message } from './message';
import * as i0 from "@angular/core";
export declare class OverlayService {
    private clickSource;
    clickObservable: import("rxjs").Observable<Message | Message[]>;
    add(event: any): void;
    static ɵfac: i0.ɵɵFactoryDeclaration<OverlayService, never>;
    static ɵprov: i0.ɵɵInjectableDeclaration<OverlayService>;
}