import { BehaviorSubject } from 'rxjs';
import * as i0 from "@angular/core";
export declare class NodeItem {
    title: string;
    children?: NodeItem[];
    data: any;
}
export declare class TreeNode {
    expandable: boolean;
    item: NodeItem;
    level: number;
    constructor(expandable: boolean, item: NodeItem, level: number);
}
export declare class TreeNodeDatabase {
    dataChange: BehaviorSubject<NodeItem[]>;
    get data(): NodeItem[];
    constructor();
    remove(node: TreeNode, parentNode: TreeNode): void;
    add(title: string, parent?: NodeItem): NodeItem;
    initialize(initData: any): void;
    static ɵfac: i0.ɵɵFactoryDeclaration<TreeNodeDatabase, never>;
    static ɵprov: i0.ɵɵInjectableDeclaration<TreeNodeDatabase>;
}