import { ISignal } from '@phosphor/signaling';
import { FocusTracker, Widget } from '@phosphor/widgets';
import { IInstanceRestorer } from '../instancerestorer';
/**
 * The application shell for JupyterLab.
 */
export declare class ApplicationShell extends Widget {
    /**
     * Construct a new application shell.
     */
    constructor();
    /**
     * A signal emitted when main area's current focus changes.
     */
    readonly currentChanged: ISignal<this, ApplicationShell.IChangedArgs>;
    /**
     * A signal emitted when main area's active focus changes.
     */
    readonly activeChanged: ISignal<this, ApplicationShell.IChangedArgs>;
    /**
     * The current widget in the shell's main area.
     */
    readonly currentWidget: Widget | null;
    /**
     * The active widget in the shell's main area.
     */
    readonly activeWidget: Widget | null;
    /**
     * True if left area is empty.
     */
    readonly leftAreaIsEmpty: boolean;
    /**
     * True if main area is empty.
     */
    readonly mainAreaIsEmpty: boolean;
    /**
     * Promise that resolves when state is restored, returning layout description.
     */
    readonly restored: Promise<IInstanceRestorer.ILayout>;
    /**
     * True if right area is empty.
     */
    readonly rightAreaIsEmpty: boolean;
    /**
     * True if top area is empty.
     */
    readonly topAreaIsEmpty: boolean;
    /**
     * Activate a widget in the left area.
     */
    activateLeft(id: string): void;
    /**
     * Activate a widget in the main area.
     */
    activateMain(id: string): void;
    activateNextTab(): void;
    activatePreviousTab(): void;
    /**
     * Activate a widget in the right area.
     */
    activateRight(id: string): void;
    /**
     * Add a widget to the left content area.
     *
     * #### Notes
     * Widgets must have a unique `id` property, which will be used as the DOM id.
     */
    addToLeftArea(widget: Widget, options?: ApplicationShell.ISideAreaOptions): void;
    /**
     * Add a widget to the main content area.
     *
     * #### Notes
     * Widgets must have a unique `id` property, which will be used as the DOM id.
     * All widgets added to the main area should be disposed after removal (or
     * simply disposed in order to remove).
     */
    addToMainArea(widget: Widget): void;
    /**
     * Add a widget to the right content area.
     *
     * #### Notes
     * Widgets must have a unique `id` property, which will be used as the DOM id.
     */
    addToRightArea(widget: Widget, options?: ApplicationShell.ISideAreaOptions): void;
    /**
     * Add a widget to the top content area.
     *
     * #### Notes
     * Widgets must have a unique `id` property, which will be used as the DOM id.
     */
    addToTopArea(widget: Widget, options?: ApplicationShell.ISideAreaOptions): void;
    /**
     * Collapse the left area.
     */
    collapseLeft(): void;
    /**
     * Collapse the right area.
     */
    collapseRight(): void;
    /**
     * Close all widgets in the main area.
     */
    closeAll(): void;
    /**
     * Set the layout data store for the application shell.
     */
    setLayoutDB(database: IInstanceRestorer.ILayoutDB): void;
    private _currentTabBar();
    private _previousTabBar();
    private _nextTabBar();
    /**
     * Save the dehydrated state of the application shell.
     */
    private _save();
    /**
     * Handle a change to the dock area current widget.
     */
    private _onCurrentChanged(sender, args);
    /**
     * Handle a change to the dock area active widget.
     */
    private _onActiveChanged(sender, args);
    private _database;
    private _dockPanel;
    private _hboxPanel;
    private _hsplitPanel;
    private _isRestored;
    private _leftHandler;
    private _restored;
    private _rightHandler;
    private _topPanel;
    private _tracker;
    private _currentChanged;
    private _activeChanged;
}
/**
 * The namespace for `ApplicationShell` class statics.
 */
export declare namespace ApplicationShell {
    /**
     * The areas of the application shell where widgets can reside.
     */
    type Area = 'main' | 'top' | 'left' | 'right';
    /**
     * The options for adding a widget to a side area of the shell.
     */
    interface ISideAreaOptions {
        /**
         * The rank order of the widget among its siblings.
         */
        rank?: number;
    }
    /**
     * An arguments object for the changed signals.
     */
    type IChangedArgs = FocusTracker.IChangedArgs<Widget>;
}