import { StackPanelClassNameContract } from "@microsoft/fast-components-class-name-contracts-base";
import Foundation, { HandledProps } from "@microsoft/fast-components-foundation-react";
import { Direction } from "@microsoft/fast-web-utilities";
import React from "react";
import { StackPanelHandledProps, StackPanelProps, StackPanelUnhandledProps } from "./stack-panel.props";
export interface StackPanelState {
    isScrollable: boolean;
    renderedRangeStartIndex: number;
    renderedRangeEndIndex: number;
    direction: Direction;
}
declare class StackPanel extends Foundation<StackPanelHandledProps, StackPanelUnhandledProps, StackPanelState> {
    static displayName: string;
    static defaultProps: Partial<StackPanelProps>;
    private static DirectionAttributeName;
    protected handledProps: HandledProps<StackPanelHandledProps>;
    private rootElement;
    /**
     * ref to the element which is the container all children are rendered into
     * It is sized accomodate all children and is the container that is being scrolled
     */
    private itemContainerElement;
    private resizeDetector;
    private itemPositions;
    private viewportSpan;
    private itemContainerSpan;
    private maxScroll;
    /**
     * Stores last scroll position from scroll events
     */
    private lastRecordedScroll;
    /**
     * Delays updating ui during scrolling
     * (to avoid rendering of items that just scroll by)
     */
    private scrollLayoutUpdateTimer;
    /**
     * constructor
     */
    constructor(props: StackPanelProps);
    /**
     * Renders the component
     */
    render(): React.ReactElement<HTMLDivElement>;
    /**
     * React life-cycle method
     */
    componentDidMount(): void;
    /**
     * React life-cycle method
     */
    componentDidUpdate(prevProps: StackPanelProps): void;
    /**
     * React life-cycle method
     */
    componentWillUnmount(): void;
    /**
     * Create class-names
     */
    protected generateClassNames(): string;
    /**
     * Render the items
     */
    private renderItems;
    /**
     * Render a single item
     */
    private renderItem;
    /**
     * Builds a list of positioning data for all items
     */
    private updateItemPositions;
    /**
     * Gets the maximum distance that can be scrolled
     */
    private getMaxScrollDistance;
    /**
     *  Get the size of the viewport along the panel's axis
     */
    private getViewportSpan;
    /**
     * Recalculates the layout
     */
    private updateLayout;
    /**
     * gets the first row where the row bottom exceeds the threshold value
     * returns final item index if no rows reach threshold value
     */
    private getThresholdItemIndex;
    /**
     * gets the current buffer size (number of items to render outside the viewport)
     */
    private getBufferLength;
    /**
     *  Handle scroll events
     */
    private onScrollCapture;
    /**
     *  Handle viewport resize events
     */
    private handleResize;
    /**
     *  report scroll changes to callback
     */
    private reportScrollChange;
    /**
     *  updates the direction in state if necessary
     */
    private updateDirection;
    /**
     *  gets the current direction
     */
    private getDirection;
    /**
     *  Gets the scroll position and accounts for direction
     */
    private getScrollPosition;
    /**
     *  Sets the scroll position and accounts for direction
     */
    private setScrollPosition;
    /**
     * Scrolls the container for the items list
     */
    private scrollContent;
    /**
     * Gets the scroll position that brings the item at a particular index into the viewport
     */
    private getScrollIntoViewPosition;
}
export default StackPanel;
export * from "./stack-panel.props";
export { StackPanelClassNameContract };