updateRenderOverflow method

void updateRenderOverflow(Element element)

Implementation

void updateRenderOverflow(Element element) {
  ScrollListener scrollListener = element.elementDelegate.handleScroll;
  CSSStyleDeclaration style = element.style;
  RenderBoxModel renderBoxModel = element.renderBoxModel!;
  RenderStyle renderStyle = renderBoxModel.renderStyle;

  renderStyle.updateOverflow(style);

  if (renderBoxModel is RenderRecyclerLayout) {
    // Recycler layout not need repaintBoundary and scroll/pointer listeners,
    // ignoring overflowX or overflowY sets, which handle it self.
    renderBoxModel.clipX = renderBoxModel.clipY = false;
    renderBoxModel.scrollOffsetX = renderBoxModel.axis == Axis.horizontal
        ? renderBoxModel.scrollable.position : null;
    renderBoxModel.scrollOffsetY = renderBoxModel.axis == Axis.vertical
        ? renderBoxModel.scrollable.position : null;
  } else {
    CSSOverflowType overflowX = renderStyle.overflowX;
    CSSOverflowType overflowY = renderStyle.overflowY;
    bool shouldRepaintSelf = false;

    switch(overflowX) {
      case CSSOverflowType.hidden:
        _scrollableX = null;
        renderBoxModel.clipX = true;
        // Overflow hidden can be scrolled programmatically.
        renderBoxModel.enableScrollX = true;
        break;
      case CSSOverflowType.clip:
        _scrollableX = null;
        renderBoxModel.clipX = true;
        // Overflow clip can't scrolled programmatically.
        renderBoxModel.enableScrollX = false;
        break;
      case CSSOverflowType.auto:
      case CSSOverflowType.scroll:
        _scrollableX = KrakenScrollable(axisDirection: AxisDirection.right, scrollListener: scrollListener);
        shouldRepaintSelf = true;
        renderBoxModel.clipX = true;
        renderBoxModel.enableScrollX = true;
        renderBoxModel.scrollOffsetX = _scrollableX!.position;
        break;
      case CSSOverflowType.visible:
      default:
        _scrollableX = null;
        renderBoxModel.clipX = false;
        renderBoxModel.enableScrollX = false;
        break;
    }

    switch(overflowY) {
      case CSSOverflowType.hidden:
        _scrollableY = null;
        renderBoxModel.clipY = true;
        renderBoxModel.enableScrollY = true;
        break;
      case CSSOverflowType.clip:
        _scrollableY = null;
        renderBoxModel.clipY = true;
        renderBoxModel.enableScrollY = false;
        break;
      case CSSOverflowType.auto:
      case CSSOverflowType.scroll:
        _scrollableY = KrakenScrollable(axisDirection: AxisDirection.down, scrollListener: scrollListener);
        shouldRepaintSelf = true;
        renderBoxModel.clipY = true;
        renderBoxModel.enableScrollY = true;
        renderBoxModel.scrollOffsetY = _scrollableY!.position;
        break;
      case CSSOverflowType.visible:
      default:
        _scrollableY = null;
        renderBoxModel.clipY = false;
        renderBoxModel.enableScrollY = false;
        break;
    }

    renderBoxModel.scrollListener = scrollListener;
    renderBoxModel.pointerListener = _pointerListener;

    if (renderBoxModel is RenderLayoutBox) {
      if (shouldRepaintSelf) {
        _upgradeToSelfRepaint(element);
      } else {
        _downgradeToParentRepaint(element);
      }
    }
  }
}