import { AfterViewInit, OnDestroy, OnInit } from '@angular/core';
import { NgbSort, NgbSortable, SortHeaderArrowPosition } from './sort';
import { SortDirection } from './sort-direction';
import * as i0 from "@angular/core";
/** Column definition associated with a `NgbSortHeader`. */
interface NgbSortHeaderColumnDef {
    name: string;
}
/**
 * Applies sorting behavior (click to change sort) and styles to an element, including an
 * arrow to display the current sort direction.
 *
 * Must be provided with an id and contained within a parent NgbSort directive.
 *
 * If used on header cells in a CdkTable, it will automatically default its id from its containing
 * column definition.
 */
export declare class NgbSortHeader implements NgbSortable, OnDestroy, OnInit, AfterViewInit {
    _sort: NgbSort;
    _columnDef: NgbSortHeaderColumnDef | null;
    private _changeDetectorRef;
    private _focusMonitor;
    private _elementRef;
    private _ariaDescriber;
    private _renderChanges;
    protected _animationModule: "NoopAnimations" | "BrowserAnimations" | null;
    /**
     * Indicates which state was just cleared from the sort header.
     * Will be reset on the next interaction. Used for coordinating animations.
     */
    protected _recentlyCleared: import("@angular/core").WritableSignal<SortDirection | null>;
    /**
     * The element with role="button" inside this component's view. We need this
     * in order to apply a description with AriaDescriber.
     */
    private _sortButton;
    /**
     * ID of this sort header. If used within the context of a CdkColumnDef, this will default to
     * the column's name.
     */
    id: string;
    /** Sets the position of the arrow that displays when sorted. */
    arrowPosition: SortHeaderArrowPosition;
    /** Overrides the sort start value of the containing NgbSort for this NgbSortable. */
    start: SortDirection;
    /** whether the sort header is disabled. */
    disabled: boolean;
    /**
     * Description applied to NgbSortHeader's button element with aria-describedby. This text should
     * describe the action that will occur when the user clicks the sort header.
     */
    get sortActionDescription(): string;
    set sortActionDescription(value: string);
    private _sortActionDescription;
    /** Overrides the disable clear value of the containing NgbSort for this NgbSortable. */
    disableClear: boolean;
    constructor(...args: unknown[]);
    ngOnInit(): void;
    ngAfterViewInit(): void;
    ngOnDestroy(): void;
    /** Triggers the sort on this sort header and removes the indicator hint. */
    _toggleOnInteraction(): void;
    _handleKeydown(event: KeyboardEvent): void;
    /** Whether this NgbSortHeader is currently sorted in either ascending or descending order. */
    _isSorted(): boolean;
    _isDisabled(): boolean;
    /**
     * Gets the aria-sort attribute that should be applied to this sort header. If this header
     * is not sorted, returns null so that the attribute is removed from the host element. Aria spec
     * says that the aria-sort property should only be present on one header at a time, so removing
     * ensures this is true.
     */
    _getAriaSortAttribute(): "none" | "ascending" | "descending";
    /** Whether the arrow inside the sort header should be rendered. */
    _renderArrow(): boolean;
    private _updateSortActionDescription;
    static ɵfac: i0.ɵɵFactoryDeclaration<NgbSortHeader, never>;
    static ɵcmp: i0.ɵɵComponentDeclaration<NgbSortHeader, "[ngb-sort-header]", ["ngbSortHeader"], { "id": { "alias": "ngb-sort-header"; "required": false; }; "arrowPosition": { "alias": "arrowPosition"; "required": false; }; "start": { "alias": "start"; "required": false; }; "disabled": { "alias": "disabled"; "required": false; }; "sortActionDescription": { "alias": "sortActionDescription"; "required": false; }; "disableClear": { "alias": "disableClear"; "required": false; }; }, {}, never, ["*"], true, never>;
    static ngAcceptInputType_disabled: unknown;
    static ngAcceptInputType_disableClear: unknown;
}
export {};