import { HttpBackend } from '@angular/common/http';
import * as i0 from "@angular/core";
export declare class VersionCheckService {
    private httpClient;
    private activeVersion;
    private timeInMinute;
    constructor(handler: HttpBackend);
    initVersionCheck(activeVersion: string, url?: string, frequency?: number): void;
    checkVersion(url: string): void;
    static ɵfac: i0.ɵɵFactoryDeclaration<VersionCheckService, never>;
    static ɵprov: i0.ɵɵInjectableDeclaration<VersionCheckService>;
}