import { ElementRef } from '@angular/core';
import { ProvidersService } from 'fccore2';
import { FcComponent } from '../fc';
import { Router } from '@angular/router';
/**
 * fc-backtop回到顶部
 *
 * 返回页面顶部的操作按钮。
 *
 * 当页面内容区域比较长时。
 *
 * 当用户需要频繁返回顶部查看相关内容时。
 *
 */
export declare class FcbacktopComponent extends FcComponent {
    provider: ProvidersService;
    elementRef: ElementRef;
    router: Router;
    /** 标题*/
    fcLabel: string;
    /**滚动到一定高度出现*/
    fcVisibilityHeight: string;
    _visibility: number;
    element1: any;
    constructor(provider: ProvidersService, elementRef: ElementRef, doc: any, router: Router);
    ngOnChanges(param: any): void;
    ngAfterViewInit(): void;
}
export interface FcbacktopOption {
    label?: string;
    href?: string;
}