Method setInnerContainerSize

core/ui/UIScrollView.cpp:175–238

}

void ScrollView::setInnerContainerSize(const Vec2& size)
{
    float innerSizeWidth   = _contentSize.width;
    float innerSizeHeight  = _contentSize.height;
    Vec2 originalInnerSize = _innerContainer->getContentSize();
    if (size.width >= innerSizeWidth)
    {
        innerSizeWidth = size.width;
    }
    if (size.height >= innerSizeHeight)
    {
        innerSizeHeight = size.height;
    }
    _innerContainer->setContentSize(Vec2(innerSizeWidth, innerSizeHeight));

    // Calculate and set the position of the inner container.
    Vec2 pos               = _innerContainer->getPosition();
    const auto boundingBox = _innerContainer->getBoundingBox();
    const auto rBoundary   = boundingBox.origin.x + boundingBox.size.width;
    const auto bBoundary   = boundingBox.origin.y;
    if (rBoundary < _contentSize.width)
    {
        // When the right border does not fit to the width,
        // consider left-side fitting or right-side fitting.
        const auto lBoundary = boundingBox.origin.x;
        if (rBoundary - lBoundary > _contentSize.width)
        {
            // The width of _innerContainer is greater than _contentSize.width,use right-side fitting.
            pos.x = _contentSize.width -
                    (1.f - _innerContainer->getAnchorPoint().x) * _innerContainer->getContentSize().width;
        }
        else
        {
            // or use left-side fitting.
            pos.x = _innerContainer->getAnchorPoint().x * _innerContainer->getContentSize().width;
        }
    }
    if (bBoundary > 0.f)
    {
        // Same as horizontal direction.
        const auto tBoundary = boundingBox.origin.y + boundingBox.size.height;
        if (tBoundary - bBoundary > _contentSize.height)
        {
            pos.y = _innerContainer->getAnchorPoint().y * _innerContainer->getContentSize().height;
        }
        else
        {
            pos.y = _contentSize.height -
                    (1.0f - _innerContainer->getAnchorPoint().y) * _innerContainer->getContentSize().height;
        }
    }
    // In the vertical direction, if the _innerContainer initially contains content larger than _contentSize.height,
    // this will result in bottom alignment.Obviously this is not what I want,
    // so here is the rule : when the height of _innerContainer and _contentSize are equal,
    // if the position of _innerContainer needs to be changed at this point,align _innerContainer to the top.
    if (Direction::VERTICAL == _direction && originalInnerSize.height == _contentSize.height)
    {
        pos.y = _contentSize.height - innerSizeHeight;