import * as i0 from "@angular/core";
export declare class TreeviewKeyboardService {
    handleKeyDown(event: KeyboardEvent, treeElement: HTMLElement): void;
    private handleArrowKey;
    onFocusIn(treeElement: HTMLElement, event: FocusEvent): void;
    onFocusOut(treeElement: HTMLElement, event: FocusEvent): void;
    initialize(treeElement: HTMLElement): void;
    static ɵfac: i0.ɵɵFactoryDeclaration<TreeviewKeyboardService, never>;
    static ɵprov: i0.ɵɵInjectableDeclaration<TreeviewKeyboardService>;
}