Basic_layout.dart

Scaffold(
    appBar: AppBar(),
    bottomNavigationBar: BottomAppBar(
        child: Container(
        height: 50.0,
        child: Row(
            children: <Widget>[
            Expanded(
                child: IconButton(
                    icon: Icon(Icons.person),
                    onPressed: () => controller.index = 0),
            ),
            Expanded(
                child: IconButton(
                    icon: Icon(Icons.notifications),
                    onPressed: () => controller.index = 1),
           ),
         ],
      ),
    ),
  ),
  body: TabBarView(
   controller: controller,
   children: [
          Center(
            child: Text("Page 1"),
          ),
          Center(
            child: Text("Page 2"),
          ),
   ]),
)