/**-----------------------------------------------------------------------------------------
* Copyright © 2025 Progress Software Corporation. All rights reserved.
* Licensed under commercial license. See LICENSE.md in the project root for more information
*-------------------------------------------------------------------------------------------*/
import { EventEmitter } from '@angular/core';
import { FilterState } from './filter-state.interface';
import { TreeItem } from './treeitem.interface';
import * as i0 from "@angular/core";
/**
 * @hidden
 *
 * An injection token used by the expand-directive to interface with
 * the TreeView or the DropDownTree components.
 */
export declare abstract class ExpandableComponent {
    /**
     * A function which determines if a specific node is expanded.
     */
    abstract isExpanded: (item: object, index: string) => boolean;
    /**
     * Fires when the user expands a TreeView node.
     */
    abstract expand: EventEmitter<TreeItem>;
    /**
     * Fires when the user collapses a TreeView node.
     */
    abstract collapse: EventEmitter<TreeItem>;
    /**
     * Emits when the built-in filtering mechanism in the data-binding directives updates the node visibility.
     * Used for the built-in auto-expand functionalities of the component and available for custom implementations.
     */
    abstract filterStateChange?: EventEmitter<FilterState>;
    static ɵfac: i0.ɵɵFactoryDeclaration<ExpandableComponent, never>;
    static ɵprov: i0.ɵɵInjectableDeclaration<ExpandableComponent>;
}