import { PropertyValues } from 'lit';
import { SpectrumElement } from '../../element/index.js';
/**
 * Base class for an individual tab within a tabbed interface.
 *
 * Manages the tab's selection state, disabled behavior, ARIA
 * attributes, and roving tabindex. Concrete classes supply the
 * stylesheet and render template.
 *
 * Disabled tabs use `aria-disabled="true"` and remain focusable via
 * arrow keys per the ARIA Authoring Practices Guide, but are not
 * activatable (Enter, Space, and click are guarded).
 *
 * @slot - Text label of the tab
 * @slot icon - Optional icon displayed before the label
 */
export declare abstract class TabBase extends SpectrumElement {
    /**
     * Whether this tab is disabled. Disabled tabs are announced as
     * unavailable by assistive technology and cannot be activated,
     * but remain focusable via arrow keys within the tablist.
     */
    disabled: boolean;
    /**
     * Whether this tab is currently selected. Managed by the parent
     * `swc-tabs` container — consumers should not set this directly.
     * Use `swc-tabs[selected]` instead.
     */
    selected: boolean;
    /**
     * Whether the tab is displayed in vertical orientation.
     *
     * Orientation is primarily driven by the parent `swc-tabs` `direction`
     * attribute; this property remains for styling and any consumers that read
     * it explicitly. We can remove it in a future major once vertical layout is
     * fully parent-driven only—track that cleanup in the component backlog if
     * it becomes redundant in practice.
     */
    vertical: boolean;
    /**
     * Unique identifier for this tab. Used by the parent `swc-tabs`
     * to match this tab to its corresponding `swc-tab-panel`.
     */
    tabId: string;
    protected firstUpdated(changes: PropertyValues): void;
    protected updated(changes: PropertyValues): void;
    private syncAriaSelected;
    private syncAriaDisabled;
}