Add customize bottom navigation bar

lib/widgets/bottom_app_bar.dart

@@ -0,0 +1,31 @@
+import 'package:flutter/material.dart';
+
+class BottomAppBar extends StatefulWidget {
+  @override
+  _BottomAppBarState createState() => _BottomAppBarState();
+}
+
+class _BottomAppBarState extends State<BottomAppBar> {
+  @override
+  Widget build(BuildContext context) {
+    return BottomNavigationBar(
+      items: const <BottomNavigationBarItem>[
+        BottomNavigationBarItem(
+          icon: Icon(Icons.home),
+          title: Text('Accueil'),
+        ),
+        BottomNavigationBarItem(
+          icon: Icon(Icons.add),
+          title: Text('Notes'),
+        ),
+        BottomNavigationBarItem(
+          icon: Icon(Icons.business),
+          title: Text('Enseignes'),
+        ),
+      ],
+
+      selectedItemColor: Colors.indigo[900],
+
+    );
+  }
+}