import { MatDialog } from '@angular/material/dialog';
import { SwUpdate } from '@angular/service-worker';
/**
 * Provides helpers for handling pwa version updates.
 */
export declare class NgxPwaUpdateService {
    private readonly swUpdate;
    private readonly dialog;
    constructor(swUpdate: SwUpdate, dialog: MatDialog);
    /**
     * Subscribes to any version update events.
     */
    subscribeToUpdateEvents(): void;
    /**
     * Gets called when no new version was found.
     */
    protected onNoNewVersionDetected(): void;
    /**
     * Gets called when the installation of a new version fails.
     */
    protected onVersionInstallationFailed(): void;
    /**
     * Gets called when a new version has been found.
     */
    protected onVersionDetected(): void;
    /**
     * Gets called when a new version has been installed.
     */
    protected onVersionReady(): Promise<void>;
    /**
     * Manually checks for updates.
     * @returns Whether or not new updates are available.
     */
    checkForUpdates(): Promise<boolean>;
}