import { BehaviorSubjectable } from '../abstract/behavior.subjectable';
import { BehaviorSubject } from '../../node_modules/rxjs';
/**
 * ScrollPositionSubject
 * =====================
 *
 * ## Usage
 *
 * By default the class will observe the window object...
 *
 * ```typescript
 * import {
 *   ScrollPositionSubject
 * } from '@mralexandernickel/frontend-subjects/dist/scroll.position/scroll.position';
 *
 * export default new ScrollPositionSubject();
 * ```
 *
 * ...if you want to observe the scroll-position of a regular element, you can
 * do this by passing the target-element to the constructor...
 *
 * ```typescript
 * import {
 *   ScrollPositionSubject
 * } from '@mralexandernickel/frontend-subjects/dist/scroll.position/scroll.position';
 *
 * const targetElement = document.getElementById('your-shiny-element');
 * export default new ScrollPositionSubject(targetElement);
 * ```
 *
 * ...at last you can subscribe to this scroll-position wherever and as often
 * as you like, without creating new event-listeners all the time 🚀
 *
 * ```typescript
 * import ScrollPosition from './ScrollPosition';
 * ScrollPosition.get().subscribe(scrollPosition => {
 *   console.log('ScrollPosition is now:', scrollPosition);
 * });
 * ```
 */
export declare class ScrollPositionSubject extends BehaviorSubjectable {
    private targetElement;
    /**
     * The scroll-position on y-axis of this.targetElement
     */
    protected subject: BehaviorSubject<number>;
    /**
     * @constructor
     */
    constructor(targetElement?: HTMLElement | Window);
    /**
     * Get the scroll-position on y-axis based on the type of this.targetElement
     * @return {number}
     */
    private getScrollYPosition;
    /**
     * Callback function for the ScrollSubject
     * @return {void}
     */
    private scrollHandler;
}