export declare class SwipeService {
    private _swipeCoord?;
    private _swipeTime?;
    /**
     * @param {TouchEvent} e
     * @param {string} when
     * @returns {number}
     * @description detect the direction of the swipe, and return a -1 or 1 if the duration is long enough
     *              else return a 0 to do nothing
     */
    swipe(e: TouchEvent, when: string): number;
}