import * as i0 from "@angular/core";
export declare class PageVisibilityService {
    private readonly pageVisibility$;
    getPageVisibility(): import("rxjs").Observable<boolean>;
    static ɵfac: i0.ɵɵFactoryDeclaration<PageVisibilityService, never>;
    static ɵprov: i0.ɵɵInjectableDeclaration<PageVisibilityService>;
}