import { ActivityData } from '../types';
export type GroupedItemData = {
    collapsed: boolean;
    timestamp: number;
    children: unknown[];
};
export declare const buildGroupedItems: any;
export type GroupItemData = {
    collapsed: boolean;
    timestamp: number;
    index: number;
};
export declare const flattenGroupedItems: any;
export declare const isGroupItem: any;
export declare const getItemKey: (index: number, data: (ActivityData | GroupItemData)[]) => string;
