devextreme/esm/renovation/ui/scroll_view/scrollable_utils.js

HTML5 JavaScript Component Suite for Responsive Web Development

/**
 * DevExtreme (esm/renovation/ui/scroll_view/scrollable_utils.js)
 * Version: 21.1.4
 * Build date: Mon Jun 21 2021
 *
 * Copyright (c) 2012 - 2021 Developer Express Inc. ALL RIGHTS RESERVED
 * Read about DevExtreme licensing here: https://js.devexpress.com/Licensing/
 */
import getScrollRtlBehavior from "../../../core/utils/scroll_rtl_behavior";
import {
    titleize
} from "../../../core/utils/inflector";
import {
    DIRECTION_VERTICAL,
    DIRECTION_HORIZONTAL,
    DIRECTION_BOTH
} from "./common/consts";
import {
    ScrollDirection
} from "./utils/scroll_direction";

function isScrollInverted(rtlEnabled) {
    var {
        decreasing: decreasing,
        positive: positive
    } = getScrollRtlBehavior();
    return rtlEnabled && !!(decreasing ^ positive)
}
export function getScrollSign(rtlEnabled) {
    return isScrollInverted(rtlEnabled) && getScrollRtlBehavior().positive ? -1 : 1
}

function getElementLocationInternal(element, offset, direction, containerElement) {
    var prop = direction === DIRECTION_VERTICAL ? "top" : "left";
    var dimension = direction === DIRECTION_VERTICAL ? "Height" : "Width";
    var relativeLocation = containerElement["scroll".concat(titleize(prop))] + element.getBoundingClientRect()[prop] - containerElement.getBoundingClientRect()[prop];
    var containerLocation = containerElement["scroll".concat(titleize(prop))];
    var scrollBarSize = containerElement["offset".concat(dimension)] - containerElement["client".concat(dimension)];
    var containerSize = containerElement["offset".concat(dimension)];
    var elementOffset = element["offset".concat(dimension)];
    var offsetStart = offset[prop];
    var offsetEnd = offset[direction === DIRECTION_VERTICAL ? "bottom" : "right"] || 0;
    if (relativeLocation < containerLocation + offsetStart) {
        if (elementOffset < containerSize - offsetStart - offsetEnd) {
            return relativeLocation - offsetStart
        }
        return relativeLocation + elementOffset - containerSize + offsetEnd + scrollBarSize
    }
    if (relativeLocation + elementOffset >= containerLocation + containerSize - offsetEnd - scrollBarSize) {
        if (elementOffset < containerSize - offsetStart - offsetEnd) {
            return relativeLocation + elementOffset + scrollBarSize - containerSize + offsetEnd
        }
        return relativeLocation - offsetStart
    }
    return containerLocation
}
export function normalizeOffsetLeft(scrollLeft, maxLeftOffset, rtlEnabled) {
    if (isScrollInverted(rtlEnabled)) {
        if (getScrollRtlBehavior().positive) {
            return maxLeftOffset - scrollLeft
        }
        return maxLeftOffset + scrollLeft
    }
    return scrollLeft
}
export function getLocation(element, offset, direction, containerElement) {
    var location = getElementLocationInternal(element, offset, direction, containerElement);
    return location
}
export function updateAllowedDirection(allowedDirections, direction) {
    var {
        isBoth: isBoth,
        isHorizontal: isHorizontal,
        isVertical: isVertical
    } = new ScrollDirection(direction);
    if (isBoth && allowedDirections.vertical && allowedDirections.horizontal) {
        return DIRECTION_BOTH
    }
    if (isHorizontal && allowedDirections.horizontal) {
        return DIRECTION_HORIZONTAL
    }
    if (isVertical && allowedDirections.vertical) {
        return DIRECTION_VERTICAL
    }
    return
}