import { QueryList, AfterViewInit, OnDestroy } from '@angular/core';
import { ScrollSpyItemDirective } from '../scroll-spy-item/scroll-spy-item.directive';
import { ScrollSpyService } from '../scroll-spy-service/scroll-spy.service';
import * as i0 from "@angular/core";
/**
 * Adds `active` class to navigation links when section is in the viewport.
 * Used in conjuction with `snScrollItem` directive which should be added
 * to anchor links in the nav
 *
 * @example
 * ```
 * <ul role="navigation" snScrollSpy id="foo">
 *  <li><a snScrollSpyItem for="foo" href="#section1">Section 1</a></li>
 *  <li><a snScrollSpyItem for="foo" href="#section2">Section 2</a></li>
 *  <li><a snScrollSpyItem for="foo" href="#section3">Section 3</a></li>
 *  <li><a snScrollSpyItem for="foo" href="#section4">Section 4</a></li>
 * </ul>
 * ```
 *
 */
export declare class ScrollSpyDirective implements AfterViewInit, OnDestroy {
    private scrollSpySvc;
    /**
     * Collection of `ScrollSpyItem`. They are the list of
     * nav items.
     *
     * @memberof ScrollSpyDirective
     */
    items: QueryList<ScrollSpyItemDirective>;
    /**
     * ID of scrollSpy instance
     *
     * @memberof ScrollSpyDirective
     */
    id: string;
    /**
     * Creates an instance of ScrollSpyDirective.
     * @memberof ScrollSpyDirective
     */
    constructor(scrollSpySvc: ScrollSpyService);
    /**
     * Adds spy to list of spys in `ScrollSpyService`
     *
     * @memberof ScrollSpyDirective
     */
    ngAfterViewInit(): void;
    /**
     * Remove spy from list of spys when directive is destroyed
     *
     * @memberof ScrollSpyDirective
     */
    ngOnDestroy(): void;
    static ɵfac: i0.ɵɵFactoryDeclaration<ScrollSpyDirective, never>;
    static ɵdir: i0.ɵɵDirectiveDeclaration<ScrollSpyDirective, "[snScrollSpy]", never, { "id": { "alias": "id"; "required": false; }; }, {}, ["items"], never, true, never>;
}