DraggableScrollableSheet 在水平拖动时重置滚动位置

Question

我正致力于在 Flutter 中的 Draggable 对象内实现 DraggableScrollableSheet。但是，当工作表向下滚动然后用户刷卡时，DraggableScrollableSheet 的垂直滚动位置将被重置。有没有办法解决这个问题并保持滚动位置？

我的 DraggableScrollableSheet 代码：

Widget build(BuildContext context) {
return Material(
    color: Colors.transparent,
    child: Align(
    alignment: Alignment.topCenter,
    child: Container(
        width: MediaQuery.of(context).size.width * 0.95,
        height: MediaQuery.of(context).size.height * 0.75,
        decoration: (BoxDecoration(
        borderRadius: BorderRadius.all(Radius.circular(16.0)),
        image:
            DecorationImage(image: NetworkImage(imgUrl), fit: BoxFit.cover),
        )),
        child: DraggableScrollableSheet(
        minChildSize: 0.25,
        initialChildSize: 0.25,
        maxChildSize: 0.9,
        builder: (BuildContext context, ScrollController scrollController) {
            return Container(
            padding: EdgeInsets.only(left: 16.0, right: 16.0),
            decoration: BoxDecoration(
                borderRadius: BorderRadius.all(
                Radius.circular(16.0),
                ),
                boxShadow: [
                BoxShadow(
                    color: Colors.black54,
                    blurRadius: 3.0,
                    spreadRadius: 0.0,
                    offset: Offset(
                    0.0,
                    -3.0,
                    ),
                )
                ],
                color: Color(0xFF3B5D76),
            ),
            child: MediaQuery.removePadding(
                context: context,
                removeTop: true,
                child: ListView.builder(
                controller: scrollController,
                itemCount: 1,
                itemBuilder: (BuildContext context, int index) {
                    return Column(
                    children: [
                        SwipeHelper(),
                        BusinessHeader(
                        title: title,
                        caption: caption,
                        description: description,
                        cost: cost,
                        stars: stars,
                        ),
                        BusinessBody(
                            title: title,
                            about: about,
                            owners: owners,
                            products: products),
                        BottomLine(),
                        BusinessFooter(
                        address: address,
                        phone: phone,
                        open: open,
                        ),
                    ],
                    );
                },
                ),
            ),
            );
        },
        ),
    ),
    ),
);
}

我的可拖动小部件代码：

Widget buildCard(business) {
SwipeCard currentBusiness = new SwipeCard(
    imgUrl: business['imgUrl'],
    title: business['title'],
    caption: business['caption'],
    description: business['description'],
    stars: business['stars'],
    cost: business['cost'],
    about: business['about'],
    owners: business['owners'],
    products: business['products'],
    address: business['address'],
    open: business['open'],
    phone: business['phone'],
);

return Draggable(
    // Creating the swiping animation only horizontally
    axis: Axis.horizontal,
    child: currentBusiness,
    feedback: currentBusiness,
    childWhenDragging: Container(),
    onDragEnd: (details) => onDragEnd(details, business),
);
}