import{type PropertyValues,type TemplateResult}from'lit';import{LyraElement}from'../../../internal/lyra-element.js';import{type LyraHeadingLevel}from'../../../internal/heading-level.js';
/**
* `<lr-empty>` — a generic empty/no-data state. First-party invention (no
* Web Awesome equivalent); fills a gap common to dashboard-style apps.
* Initial and reconnect content are not announced as new live updates unless `announce` opts in;
* with it set, the heading/description present when the empty state first mounts is announced once
* through the same polite sink, while reconnection and adoption still stage the existing content
* instead of replaying it. Later meaningful heading
* or description changes are appended to Lyra's shared light-DOM polite announcement sink;
* decorative icon and action slots, hidden/inert content, and unchanged accessible text are not.
* A visibility-hidden wrapper omits its own text but can contain a visible override descendant.
* Nested forwarding slots contribute flattened assigned heading/description text rather than
* fallback content; later assignment and assigned-content mutations are observed without making
* initial distribution live. Updates while the host or a composed ancestor is not
* rendered/accessibility-visible stay silent. A host `aria-label` names the host only and does not
* replace visible heading/description text in the announcement sink. Property and rich-slot
* headings default to semantic level 3; set `heading-level` from `1`–`6` to fit the surrounding
* outline, or `none` for visual-only heading text.
*
* Removing heading or description safely omits that text; explicit empty values remain empty and later values restore the corresponding content.
*
* @customElement lr-empty
* @slot - Custom icon or illustration (defaults to none).
* @slot heading - Rich heading content (overrides the `heading` attribute) inside the configured
*   semantic heading wrapper.
* @slot description - Rich description content (overrides the `description` attribute).
* @slot actions - Buttons/links shown below the description.
* @csspart base - The outer container.
* @csspart icon - The wrapper around the default-slotted icon/illustration.
* @csspart heading - The heading paragraph (`role="heading"` at the configured level unless opted out).
* @csspart description - The description paragraph.
* @csspart actions - The wrapper around the `actions`-slotted content.
* @cssprop --lr-empty-compact-align - Cross-axis and text alignment used in compact mode;
* set to `center` for dense but centered empty states.
* @cssprop [--lr-empty-compact-padding=var(--lr-space-xs)] - Padding used in compact mode;
* accepts any padding shorthand (e.g. `8px 2px`).
* @cssprop [--lr-empty-compact-gap=var(--lr-space-2xs)] - Gap between the icon, title, and
* description in compact mode.
* @cssprop --lr-empty-compact-font-size - Heading font size used in compact mode. Unset by
* default (no fallback), so the heading keeps its ordinary inherited font size until a consumer
* opts in.
* @status stable
* @since 4.0.0
*/
export declare class LyraEmpty extends LyraElement{static styles:import("lit").CSSResultGroup[];
/** Short heading, e.g. "No results". */
heading:string;
/** Semantic level of the visible property/slotted heading. Use `none` for visual-only text;
*  invalid untyped values use level 3. */
headingLevel:LyraHeadingLevel;
/** Supporting copy, e.g. "Try a different search." */
description:string;
/**
* Compact rendering for use inside a constrained space (e.g. a widget body
* or table cell) rather than as a full-page state: left-aligned, tighter
* padding, and a lighter heading weight instead of the centered/spacious
* default.
*/
compact:boolean;
/** Opts this empty state into announcing the heading/description it already carries when it
*  first mounts, through the same shared light-DOM polite sink later changes use. Leave unset
*  for an empty state that is part of the page a user is arriving on: its text is read in
*  document order and repeating it is noise. Set it where the empty state replaces a result set
*  the user just asked for. This is read once, when the component first mounts -- a later
*  reconnection or adoption stages the existing content again rather than replaying it, and
*  later heading/description changes are announced either way. Remove any host
*  `role="status"`/`role="alert"` hand-added before this property existed once it is set --
*  otherwise the initial text is announced twice, through the native role and again through the
*  shared sink. */
announce:boolean;private readonly slotPresence;private contentObserver?;private announcementSink?;private announcementsArmed;private initialContentAnnounced;private announcementGeneration;private lastAnnouncementText;connectedCallback():void;disconnectedCallback():void;protected updated(changed:PropertyValues):void;firstUpdated(changed:PropertyValues):void;private reconcileSlotHidden;private announcementObservationOptions;private announcementForwardingSlots;private observeAnnouncementContent;private onForwardedSlotChange;
/** Light-DOM mutation delivery precedes the slotchange/Lit update that unhides the corresponding
* heading or description wrapper. Reconcile those two wrappers from the already-current native
* slot assignment before extracting text, so the observer's coalesced mutation batch produces
* one complete announcement instead of an intermediate heading-only entry. */
private scheduleAnnouncement;private slotContent;private announcementText;private announceCurrentContent;render():TemplateResult;}declare global{interface HTMLElementTagNameMap{'lr-empty':LyraEmpty;}}