import { TimeWheelEvent, TimeWheelEventData } from '../types';
import { BaseObserver } from './BaseObserver';
type EventCallback = (data: TimeWheelEventData) => void;
export declare class CallbackObserver extends BaseObserver {
    private callbacks;
    constructor();
    on(event: TimeWheelEvent, callback: EventCallback): void;
    off(event: TimeWheelEvent, callback: EventCallback): void;
    offAll(event?: TimeWheelEvent): void;
    protected handleEvent(data: TimeWheelEventData): void;
}
export {};
//# sourceMappingURL=CallbackObserver.d.ts.map