BottomAppBar

Scaffold(
        appBar: AppBar(
          title: Text('DEMO'),
        ),
        body: Column(),
        floatingActionButton: FloatingActionButton(
          onPressed: () {},
          child: Icon(Icons.icecream),
        ),
        floatingActionButtonLocation: FloatingActionButtonLocation.centerDocked,
        bottomNavigationBar: BottomAppBar(
          shape: CircularNotchedRectangle(),
          child: Row(
            mainAxisAlignment: MainAxisAlignment.spaceBetween,
            children: [
              IconButton(
                icon: Icon(Icons.calendar_today_sharp),
                onPressed: () {},
              ),
              IconButton(
                icon: Icon(Icons.settings),
                onPressed: () {},
              ),
            ],
          ),
        ))