Sliver:
CustomScrollView
SliverAppBar(Appbar)
SliverList(ListView)
SliverGrid(GridView)
SliverPersistentHeader (会收缩起来的控件,放在任意地方)
SliverToBoxAdapter(用于在sliver中放普通控件)
https://blog.csdn.net/yumi0629/article/details/83305627
下拉刷新控件
RefreshIndicator 如果不能拉取出来则选择将内部布局外套一层CustomScrollView