seng-scroll-tracker/lib/ScrollTrackerPoint.d.ts

Class that keeps track of the vertical scroll position of an element.

import EventDispatcher from 'seng-event';
import Side from './enum/Side';
import ScrollTracker from './ScrollTracker';
/**
 * Instance created for every coordinate that a ScrollTracker tracks.
 */
declare class ScrollTrackerPoint extends EventDispatcher {
    private scrollPosition;
    private pointHeight;
    private pointSide;
    private pointTracker;
    /**
     * Boolean indicating if the point is currently in view. Updated when checkInView() is called.
     */
    isInView: boolean;
    /**
     * Boolean indicating if the point is currently within the bounds of the target element.
     * Updated when checkInView() is called.
     */
    isInBounds: boolean;
    /**
     * Boolean indicating if the top of the viewport has been scrolled beyond this point
     */
    hasScrolledBeyond: boolean;
    constructor(scrollPosition: number, pointHeight: number, pointSide: Side, pointTracker: ScrollTracker);
    /**
     * Change the position of this point. Executes checkInView to check if the point has entered or
     * leaved view.
     * @param position The position of this points in pixels. This is the distance from the start
     * or end of the target element depending on the 'side' parameter, measured horizontally or
     * vertically depending on the axis of this ScrollTracker instance.
     */
    /**
    * @returns {number} The current position of the point in pixels. This is the distance from the
    * start or end of the target element depending on the 'side' parameter, measured horizontally or
    * vertically depending on the axis of this ScrollTracker instance.
    */
    position: number;
    /**
     * Change the height of this point. Executes checkInView to check if the point has entered or
     * leaved view.
     * @param height The height of this points in pixels. This is the distance from the start
     * or end of the target element depending on the 'side' parameter, measured horizontally or
     * vertically depending on the axis of this ScrollTracker instance.
     */
    /**
    * @returns {number} The current height of the point in pixels. This is the distance from the
    * start or end of the target element depending on the 'side' parameter, measured horizontally or
    * vertically depending on the axis of this ScrollTracker instance.
    */
    height: number;
    /**
     * @returns {Side} The side of from which the position of this point is measured.
     */
    readonly side: Side;
    private getInViewValue;
    private checkScrollBeyond;
    /**
     * Checks if this point is in view using it's position and the current scroll position saved on
     * the ScrollTracker. Updates the isInView property accordingly.
     * @return {boolean} True if this point is in view.
     */
    checkInView(scrollingBack?: boolean): boolean;
    /**
     * Disposes the ScrollTrackerPoint instance.
     */
    dispose(): void;
}
export default ScrollTrackerPoint;