use navigation rail instead of listview

ui/lib/main.dart

@@ -88,12 +88,13 @@ class _MyHomePageState extends State<MyHomePage> {
         // the App.build method, and use it to set our appbar title.
         title: Text(widget.title),
       ),
-      body: const Center(
+      body: Center(
           // Center is a layout widget. It takes a single child and positions it
           // in the middle of the parent.
           child: Row(
         children: <Widget>[
           NavDrawer(),
+          const VerticalDivider(thickness: 1, width: 1),
           SearchPage(),
         ],
       )),