import { BehaviorSubject, Observable } from 'rxjs';
import { NavItem } from '../models';
export declare abstract class AbstractMenuService<T extends NavItem> {
    protected abstract baseClass: any;
    protected _items$: BehaviorSubject<T[]>;
    get items(): T[];
    get items$(): Observable<T[]>;
    addItems(newItems: T[]): void;
    removeItem(id: string | number): void;
    patchItem(id: string | number, item: Partial<Omit<T, 'id'>>): void;
    private sortItems;
}