build in _ImprovedDraggableScrollableSheetState

improved_draggable_scrollable_sheet.dart

class _ImprovedDraggableScrollableSheetState extends State<ImprovedDraggableScrollableSheet> {

  @override
  Widget build(BuildContext context) {
    final MediaQueryData mediaQueryData = MediaQuery.of(context);
    final double heightOfDevice = mediaQueryData.size.height;
    final initialChildSize =
        (commentsHeaderHeight + mediaQueryData.viewPadding.bottom + mediaQueryData.viewPadding.top) / heightOfDevice;

    return DraggableScrollableSheet(
      initialChildSize: initialChildSize,
      minChildSize: initialChildSize,
      maxChildSize: 1.0,
      builder: (context, scrollController) {
        return Container(
          padding: EdgeInsets.only(bottom: mediaQueryData.viewPadding.bottom),
          margin: EdgeInsets.only(top: mediaQueryData.viewPadding.top),
          decoration: const BoxDecoration(
            color: Color(0xffB1B2ff),
            borderRadius: BorderRadius.vertical(top: Radius.circular(16)),
          ),
          child: Column(
            mainAxisAlignment: MainAxisAlignment.start,
            children: [
              _StreamerPageCommentsHeader(key: commentsHeaderKey, scrollController: scrollController),
              Expanded(
                child: ListView.builder(
                  padding: EdgeInsets.zero,
                  itemCount: 30,
                  itemBuilder: (context, index) => Container(
                    color: index % 2 == 0 ? const Color(0xffAAC4FF) : const Color(0xffD2DAFF),
                    child: ListTile(title: Text('Comment $index')),
                  ),
                ),
              )
            ],
          ),
        );
      },
    );
  }
}