How to use DraggableScrollableSheet for my project

I am building an array of tiles. In some cases they exist offscreen vertically. I want to be able to drag/scroll this content on screen. I am using DraggableScrollableSheet. but with my example code I get the following error:

The following assertion was thrown while applying parent data.:
Incorrect use of ParentDataWidget.

The ParentDataWidget Flexible(flex: 1) wants to apply ParentData of type FlexParentData to a RenderObject, which has been set up to accept ParentData of incompatible type BoxParentData.

Usually, this means that the Flexible widget has the wrong ancestor RenderObjectWidget. Typically, Flexible widgets are placed directly inside Flex widgets.
The offending Flexible is currently placed inside a Padding widget.

The ownership chain for the RenderObject that received the incompatible parent data was:
Padding ← Container ← Flexible ← Padding ← Container ← _BodyBuilder ← MediaQuery ← LayoutId-[<_ScaffoldSlot.body>] ← CustomMultiChildLayout ← AnimatedBuilder ← ⋯
When the exception was thrown, this was the stack

I don’t know how to fix that.

Here is my code:

@override
  Widget build(BuildContext context) {
    return Scaffold(
      body: _buildBodyScroll(),
    );
  }

  Widget _buildBodyScroll() {
    return DraggableScrollableSheet(
	initialChildSize: 0.9,
	minChildSize: 0.1,
	maxChildSize: 0.9,
	builder: (context, scrollController) {
		return SingleChildScrollView(
			controller: scrollController,
      child: _buildStackView(),
		);
  });
 }

  Widget _buildStackView() {
    return Flexible(
      child: Container(
        padding: EdgeInsets.all(0.0),
        child: Stack(
          alignment: AlignmentDirectional.center,
          children: <Widget>[
                Image.asset(
                  dashboard.bgndImage,
                  width: width,
                  height: height,
                  fit: BoxFit.cover,
                ),
            CustomMultiChildLayout(
              delegate: _DashboardLayoutDelegate(
                itemCount: tileList.length,
                tileWidth: tileWidth,
              ),
              children: tiles,
            ),
...

please help

I decided to abandon that code in favor of this:

return SingleChildScrollView(
      scrollDirection: Axis.vertical,
      child: Container(
        width: width,
        height: calcMaxTileHeight,
        decoration: BoxDecoration(
          image: DecorationImage(
              image: AssetImage(dashboard.bgndImage),
              fit: BoxFit.cover,
              repeat: ImageRepeat.noRepeat),
        ),
        child: CustomMultiChildLayout(
          delegate: _DashboardLayoutDelegate(
            itemCount: tileList.length,
            tileWidth: tileWidth,
          ),
          children: tiles,
        ),
      ),
    );

it works fine now.