import { MemoryService } from '../base/memoryService';
import { Service } from '../base/service';
export interface FocusService extends Service {
    readonly isActive: boolean;
    readonly isPendingFocus?: boolean;
    /** Whether the state is based memory, rather than a live element. */
    readonly isDisconnected?: boolean;
    setActive(isActive: boolean): void;
    focus(): void;
    blur(): void;
}
export declare const NULL_FOCUS_SERVICE: FocusService;
export declare function createMemoryFocusService(): FocusService;
export declare class MemoryFocusService extends MemoryService<boolean> implements FocusService {
    readonly isDisconnected = true;
    get isActive(): boolean;
    setActive(isActive: boolean): void;
    focus(): void;
    blur(): void;
}