import { ElementRef } from '@angular/core';
import { AppRoot } from '../app/app';
/**
 * @private
 */
export declare class Backdrop {
    private _appRoot;
    private _elementRef;
    private static nuBackDrops;
    private static push(appRoot);
    private static pop(appRoot);
    private pushed;
    disableScroll: boolean;
    constructor(_appRoot: AppRoot, _elementRef: ElementRef);
    ngOnInit(): void;
    ngOnDestroy(): void;
    getNativeElement(): HTMLElement;
}
