/**
 * @license
 * Copyright 厦门乾元盛世科技有限公司 All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file.
 */
import { ElementRef, Renderer } from '@angular/core';
import { ButtonGroup } from '../button/button.group';
import { Button } from '../button/button';
import { Menu } from '../menu/menu';
export declare type DropdownPlacement = 'topLeft' | 'topCenter' | 'topRight' | 'bottomLeft' | 'bottomCenter' | 'bottomRight';
/**
 * Dropdown Button
 */
export declare class DropdownButton extends ButtonGroup {
    private renderer;
    private elementRef;
    dropdownPrefixCls: string;
    /**
     * 菜单弹出位置：`bottomLeft` `bottomCenter` `bottomRight` `topLeft` `topCenter` `topRight`
     */
    placement: DropdownPlacement;
    /**
     * 按钮组中的第一个按钮
     */
    button: Button;
    /** 菜单 */
    menu: Menu;
    constructor(renderer: Renderer, elementRef: ElementRef);
    /**
     * The underlying host native element
     */
    getHostElement(): HTMLElement;
    /**
     * 最终样式
     */
    readonly classes: string;
    readonly buttonType: string;
    readonly disabled: boolean;
}