import { AfterContentInit, OnDestroy } from '@angular/core';
import { _RxVirtualView, _RxVirtualViewContent, _RxVirtualViewPlaceholder } from './model';
import * as i0 from "@angular/core";
/**
 * The RxVirtualView directive is a directive that allows you to create virtual views.
 *
 * It can be used on an element/component to create a virtual view.
 *
 * It works by using 3 directives:
 * - `rxVirtualViewContent`: The content to render when the virtual view is visible.
 * - `rxVirtualViewPlaceholder`: The placeholder to render when the virtual view is not visible.
 * - `rxVirtualViewObserver`: The directive that observes the virtual view and emits a boolean value indicating whether the virtual view is visible.
 *
 * The `rxVirtualViewObserver` directive is mandatory for the `rxVirtualView` directive to work.
 * And it needs to be a sibling of the `rxVirtualView` directive.
 *
 * @example
 * ```html
 * <div rxVirtualViewObserver>
 *   <div rxVirtualView>
 *     <div *rxVirtualViewContent>Virtual View 1</div>
 *     <div *rxVirtualViewPlaceholder>Loading...</div>
 *   </div>
 * </div>
 * ```
 *
 * @developerPreview
 */
export declare class RxVirtualView implements AfterContentInit, _RxVirtualView, OnDestroy {
    #private;
    /**
     * Useful when we want to cache the templates and placeholders to optimize view rendering.
     *
     * Enabled by default.
     */
    readonly cacheEnabled: import("@angular/core").InputSignalWithTransform<boolean, unknown>;
    /**
     * Whether to start with the placeholder asap or not.
     *
     * If `true`, the placeholder will be rendered immediately, without waiting for the content to be visible.
     * This is useful when you want to render the placeholder immediately, but you don't want to wait for the content to be visible.
     *
     * This is to counter concurrent rendering, and to avoid flickering.
     */
    readonly startWithPlaceholderAsap: import("@angular/core").InputSignalWithTransform<boolean, unknown>;
    /**
     * This will keep the last known size of the host element while the content is visible.
     */
    readonly keepLastKnownSize: import("@angular/core").InputSignalWithTransform<boolean, unknown>;
    /**
     * Whether to use content visibility or not.
     *
     * It will add the `content-visibility` CSS class to the host element, together with
     * `contain-intrinsic-width` and `contain-intrinsic-height` CSS properties.
     */
    readonly useContentVisibility: import("@angular/core").InputSignalWithTransform<boolean, unknown>;
    /**
     * Whether to use containment or not.
     *
     * It will add `contain` css property with:
     * - `size layout paint`: if `useContentVisibility` is `true` && placeholder is visible
     * - `content`: if `useContentVisibility` is `false` || content is visible
     */
    readonly useContainment: import("@angular/core").InputSignalWithTransform<boolean, unknown>;
    /**
     * The strategy to use for rendering the placeholder.
     */
    readonly placeholderStrategy: import("@angular/core").InputSignal<string>;
    /**
     * The strategy to use for rendering the content.
     */
    readonly contentStrategy: import("@angular/core").InputSignal<string>;
    /**
     * A function extracting width & height from a ResizeObserverEntry
     */
    readonly extractSize: import("@angular/core").InputSignal<(entry: ResizeObserverEntry) => {
        width: number;
        height: number;
    }>;
    /**
     * ResizeObserverOptions
     */
    readonly resizeObserverOptions: import("@angular/core").InputSignal<ResizeObserverOptions>;
    readonly size: import("@angular/core").WritableSignal<{
        width: number;
        height: number;
    }>;
    readonly width: import("@angular/core").Signal<string>;
    readonly height: import("@angular/core").Signal<string>;
    readonly containment: import("@angular/core").Signal<"size layout paint" | "content">;
    readonly intrinsicWidth: import("@angular/core").Signal<string>;
    readonly intrinsicHeight: import("@angular/core").Signal<string>;
    readonly minHeight: import("@angular/core").Signal<string>;
    readonly minWidth: import("@angular/core").Signal<string>;
    constructor();
    ngAfterContentInit(): void;
    ngOnDestroy(): void;
    registerContent(content: _RxVirtualViewContent): void;
    registerPlaceholder(placeholder: _RxVirtualViewPlaceholder): void;
    /**
     * Shows the content using the configured rendering strategy (by default: normal).
     * @private
     */
    private showContent$;
    /**
     * Shows the placeholder using the configured rendering strategy (by default: low).
     * @private
     */
    private showPlaceholder$;
    /**
     * Renders a placeholder within the view container, and hides the content.
     *
     * If we already have a content and cache enabled, we store the content in
     * the cache, so we can reuse it later.
     *
     * When we want to render the placeholder, we try to get it from the cache,
     * and if it is not available, we create a new one.
     *
     * Then insert the placeholder into the view container and trigger a CD.
     */
    private renderPlaceholder;
    static ɵfac: i0.ɵɵFactoryDeclaration<RxVirtualView, never>;
    static ɵdir: i0.ɵɵDirectiveDeclaration<RxVirtualView, "[rxVirtualView]", never, { "cacheEnabled": { "alias": "cacheEnabled"; "required": false; "isSignal": true; }; "startWithPlaceholderAsap": { "alias": "startWithPlaceholderAsap"; "required": false; "isSignal": true; }; "keepLastKnownSize": { "alias": "keepLastKnownSize"; "required": false; "isSignal": true; }; "useContentVisibility": { "alias": "useContentVisibility"; "required": false; "isSignal": true; }; "useContainment": { "alias": "useContainment"; "required": false; "isSignal": true; }; "placeholderStrategy": { "alias": "placeholderStrategy"; "required": false; "isSignal": true; }; "contentStrategy": { "alias": "contentStrategy"; "required": false; "isSignal": true; }; "extractSize": { "alias": "extractSize"; "required": false; "isSignal": true; }; "resizeObserverOptions": { "alias": "resizeObserverOptions"; "required": false; "isSignal": true; }; }, {}, never, never, true, never>;
}