CustomScrollView（颤振）中的动态项（条）

Question

我对CustomScrollView有问题。 这是主窗口小部件的代码：

        slivers: [
          SliverAppBar(
            expandedHeight: 414.0,
            backgroundColor: Colors.white,
            leadingWidth: 0.0,
            leading: Container(),
            flexibleSpace: _header(context, _provider),
          ),
          SliverAppBar(
              backgroundColor: Colors.white,
              flexibleSpace: _tabBar(context, _provider)),

              SliverList(delegate: SliverChildBuilderDelegate((context, index) => _tabs(context, _provider), childCount: 1)),

        ],
      ),

这是_tab方法代码：

  _tabs(BuildContext context, UserProfileProvider _provider) {
    switch (_provider.userTab) {
      case 0:
        return _GridView();
      case 1:
        return _trophyChart(context, _provider);
      case 2:
        return   _achivements(BuildContext context, UserProfileProvider _provider)
    }
  }

当我尝试从_achivements返回小部件时，出现错误。如果将小部件从_achivements放置到主小部件，则错误消失。但是在我的项目中，条子必须是动态的。

我还尝试过将_achivenets的碎片作为列表返回，并返回每个小部件，例如：

_achivements(BuildContext context, UserProfileProvider _provider).forEach((element) => element)

以下是_achivements的源代码：

 List<Widget> _achivements(BuildContext context, UserProfileProvider _provider) {
    return [
      SliverAppBar(
        backgroundColor: ThemeDefaults.primaryColor,
        pinned: true,
        leading: Container(),
        bottom: PreferredSize(
          preferredSize: Size(100, 0),
          child: DefaultTabController(
            length: 2,
            child: TabBar(
              indicatorColor: Colors.white,
              unselectedLabelStyle: GoogleFonts.raleway(
                  fontSize: 14.0,
                  fontWeight: FontWeight.w500,
                  color: Colors.white.withOpacity(0.9)),
              labelStyle: GoogleFonts.raleway(
                  fontSize: 14.0,
                  fontWeight: FontWeight.w600,
                  color: Colors.white),
              tabs: [
                Tab(text: 'IN PROGRESS'),
                Tab(text: 'COMPLETED'),
              ],
            ),
          ),
        ),
      ),
      SliverAppBar(
        pinned: true,
        backgroundColor: Theme.of(context).scaffoldBackgroundColor,
        expandedHeight: 40.0,
        leading: Container(),
        flexibleSpace: Padding(
          padding: EdgeInsets.symmetric(horizontal: 28.0, vertical: 15.0),
          child: Row(
            mainAxisAlignment: MainAxisAlignment.spaceBetween,
            children: [
              Text(
                'Completed IRLAs',
                style: GoogleFonts.raleway(
                    fontFeatures: [FontFeature.enable('lnum')],
                    fontSize: 24.0,
                    fontWeight: FontWeight.bold,
                    color: Colors.black),
              ),
              GestureDetector(
                onTap: () => showModalBottomSheet(
                  context: context,
                  builder: (BuildContext context) {
                    return GestureDetector(
                      onTap: () => Navigator.pop(context),
                      child: DraggableScrollableSheet(
                        initialChildSize: 0.1,
                        maxChildSize: 1.0,
                        minChildSize: 0.1,
                        builder: (BuildContext context,
                            ScrollController scrollController) {
                          return Container(
                            height: 100.0,
                            color: Colors.white,
                            child: Text('123'),
                          );
                        },
                      ),
                    );
                  },
                ),
                child: Container(
                  child: SvgPicture.asset('assets/img/filter.svg'),
                ),
              )
            ],
          ),
        ),
      ),
      SliverGrid(
        gridDelegate:
        SliverGridDelegateWithFixedCrossAxisCount(crossAxisCount: 2),
        delegate: SliverChildBuilderDelegate(
              (BuildContext context, int index) {
            return Container(
              margin: EdgeInsets.all(10.0),
              decoration: BoxDecoration(color: Colors.white, boxShadow: [
                BoxShadow(
                    color: ThemeDefaults.inactiveColor,
                    offset: Offset(0, 2),
                    blurRadius: 2.0,
                    spreadRadius: 0.0)
              ]),
              child: Padding(
                padding: const EdgeInsets.all(16.0),
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.center,
                  children: [
                    CircleAvatar(
                      radius: 40,
                      backgroundImage: NetworkImage(
                          _provider.mockedTrophies[index].imageURL),
                      child: Align(
                        alignment: Alignment.bottomRight,
                        child: _provider.mockedTrophies[index].trophyType ==
                            TrophyType.verified
                            ? Image.asset(
                          'assets/img/checkmark_verified.png',
                          width: 24.0,
                        )
                            : null, //_getUserCheckMark(),
                      ),
                    ),
                    SizedBox(
                      height: 18,
                    ),
                    Row(
                      mainAxisAlignment: MainAxisAlignment.center,
                      children: [
                        Text(
                          _provider.mockedTrophies[index].name,
                          style: GoogleFonts.raleway(
                              fontFeatures: [FontFeature.enable('lnum')],
                              fontSize: 18,
                              fontWeight: FontWeight.bold),
                        ),
                      ],
                    ),
                    SizedBox(
                      height: 10,
                    ),
                    Row(
                      mainAxisAlignment: MainAxisAlignment.center,
                      children: [
                        Text(
                          '${_provider.mockedTrophies[index].points} points',
                          style: GoogleFonts.raleway(
                              fontFeatures: [FontFeature.enable('lnum')],
                              fontSize: 16.84,
                              fontWeight: FontWeight.normal),
                        ),
                      ],
                    ),
                  ],
                ),
              ),
            );
          },
          childCount: _provider.mockedTrophies.length,
        ),
      ),
      ];

  }

我不知道该如何解决。如果有人有主意，请帮忙。