解决 Flutter How to Rebuild a page inside an IndexedStack

builder: (context, scrollController) {
            return SidebarItems(
              currentIndex: _pageIndex,
              onChanged: (index) {
                if (index == 2) {
                  _pages.removeAt(2);
                  _pages.insert(2, HistoryPage(key: GlobalKey()));
                }
                setState(() => _pageIndex = index);
              },
              items: _sides,
            );
},