import * as React from "react";
import LockStack, { LockListener } from "./LockStack";
export declare const LOCK_STACK: LockStack;
/**
 * Creates a subscription to the lock stack that is bound to the lifetime
 * of the caller, based on `useEffect`.
 */
export declare function useLockSubscription(callback: LockListener): void;
/**
 * Set up a return of focus to the target element specified by `returnTo` to
 * occur at the end of the lifetime of the caller component. In other words,
 * return focus to where it was before the caller component was mounted.
 */
export declare function useFocusReturn(returnRef?: React.RefObject<HTMLElement>, disabledRef?: React.RefObject<boolean>): void;
/**
 * Create and push a new lock onto the global LOCK_STACK, tied to the lifetime
 * of the caller. Returns a ref containing the current enabled state of the
 * layer, to be used for enabling/disabling the caller's lock logic.
 */
export declare function useLockLayer(controlledUID?: string): React.MutableRefObject<boolean>;
export declare type FocusLockOptions = {
    returnRef?: React.RefObject<HTMLElement>;
    disableReturnRef?: React.RefObject<boolean>;
    attachToRef?: React.RefObject<HTMLElement | Document>;
    disable?: boolean;
};
export declare function useFocusLock(containerRef: React.RefObject<HTMLElement>, options?: FocusLockOptions): void;
export default useFocusLock;
/**
 * A convenience component for rendering "guard elements" that ensure there is
 * always a tabbable element either before or after (or both) an active lock.
 * These are most easily rendered right at the edges of the React rendering root
 * so that all locks can utilize the same guards.
 *
 * When no lock is active, `FocusGuard` is completely invisible, both visually
 * and in the focus order. When active, it gets a tabindex, but always remains
 * visually hidden.
 */
export declare const FocusGuard: React.MemoExoticComponent<() => JSX.Element>;