Functional Navbar + New icons

switch between pages with pageprovider

lib/providers/pageProvider.dart

@@ -1,5 +1,17 @@
 import 'package:flutter/material.dart';
+import 'package:mensaapp/pages/pageAmbiente.dart';
+import 'package:mensaapp/pages/pageEssen.dart';
 
 class PageProvider extends ChangeNotifier {
+  int selectedPage = 0;
 
+  List<Widget> pages = [
+    const PageEssen(),
+    const PageAmbiente()
+  ];
+
+  void changePage(int index) {
+    selectedPage = index;
+    notifyListeners();
+  }
 }