import { ChangeDetectorRef } from '@angular/core';
/**
 * A directive used to add an `active` class to a nav item
 * when the section is in the viewport
 *
 * @example
 * ```html
 * <a snScrollSpyItem for="foo" href="#section1">Section 1</a>
 * ```
 *
 */
export declare class ScrollSpyItemDirective {
    private cdRef;
    /**
     * True if the nav item is the active item in the `items` list
     * for `ScrollSpyDirective` instance
     *
     * @memberof ScrollSpyItemDirective
     */
    active: boolean;
    /**
     * ID of `ScrollSpyDirective` instance
     *
     * @memberof ScrollSpyItemDirective
     */
    for: string;
    /**
     * Hash for section to link to
     *
     * @memberof ScrollSpyItemDirective
     */
    href: string;
    /**
     * If true means the section is in the viewport
     *
     * @memberof ScrollSpyItemDirective
     */
    inViewport: boolean;
    /**
     * Id of section that links navigates to
     *
     * @readonly
     * @memberof ScrollSpyItemDirective
     */
    readonly section: string;
    /**
     * Creates an instance of ScrollSpyItemDirective.
     * @memberof ScrollSpyItemDirective
     */
    constructor(cdRef: ChangeDetectorRef);
    /**
     * Manually trigger change detection
     *
     * @memberof ScrollSpyItemDirective
     */
    detectChanges(): void;
}