flutter中list view加一个header view

body:   CustomScrollView(
        slivers: <Widget>[

          SliverGrid.count(
           //具体的配置
          ),
          
          
          //列表
          SliverFixedExtentList(
            delegate: SliverChildBuilderDelegate(
                  (context, index) => ConversationListItem(
                      delegate: this, conversation: conList[index]
                  ),
              childCount: conList.length,
            ),
            itemExtent: 100,
          ),
        ],
      ),

解析：大的容器叫做custom scroll view,子控件叫做slivers，是一个数组，在数组里面从上到下排布sliver控件，有sliver grid，有sliver fixed extent list

• 效果大概长这样